+1.5053449392  |  footc@mac.com

Un-Sit Your Life

Prolonged Sitting Studies



Appetite

Appetite regulation in response to sitting and energy imbalance.

Appl Physiol Nutr Metab. 2012 Apr;37(2):323-33. doi: 10.1139/ h2012-002. Epub 2012 Mar 30. Granados K, Stephens BR, Malin SK, Zderic TW, Hamilton MT, Braun B.
Source

Department of Kinesiology, University of Massachusetts, Amherst, Amherst, MA 01003, USA. Abstract

The impact of sitting and energy imbalance on appetite and appetite- regulating hormones (acy- lated ghrelin and leptin) was assessed in response to 1 day of sitting, with and without changes in energy intake. Fourteen men and women completed each of three 24-h conditions: high energy expenditure (standing) with energy balance (STAND), low energy expenditure (sitting) with energy surplus (SIT), and sitting with energy balance (SIT-BAL). Ghrelin, leptin, and appetite were measured in the fasted state and following a standardized meal. In the fasted state, there were no differences among conditions. Following the meal, ghrelin was lower in SIT than in STAND, with no change in appetite. When intake was reduced (SIT-BAL), the decrease in ghrelin when sitting was attenuated, hunger increased, and fullness decreased. SIT led to lower

ghrelin concentrations in the men, whereas in the women, leptin increased. SIT-BAL led to an increase in ghrelin in the men but attenuated the leptin response, reduced ghrelin, increased hunger, and decreased fullness in the women. Because a dramatic reduction in energy expenditure was not accompanied by reduced appetite, prolonged sitting may promote excess energy intake, leading to weight gain in both men and women.

PMID: 22462636

Atherosclerosis

Influence of leisure time physical activity and television watching on atherosclerosis risk factors in the NHLBI Family Heart Study.

Kronenberg F, Pereira MA, Schmitz MK, Arnett DK, Evenson KR, Crapo RO, Jensen RL, Burke GL, Sholinsky P, Ellison RC, Hunt SC. Atherosclerosis. 2000 Dec;153(2):433-43.
Source

Cardiovascular Genetics, University of Utah, Salt Lake City, USA.

florian.kronenberg@uibk.ac.at Abstract

Physical activity favorably influences atherosclerosis risk factors but only a few studies in adults considered the time watching television (TV) as a measure of physical inactivity. We therefore determined in a population-based sample of 1778 subjects from the NHLBI Family Heart Study (FHS) whether leisure time physical activity and TV watching have independent or interactive associations with cardiovascular disease risk factors and carotid artery intima-media wall thick- ness (IMT). Subjects were free from diabetes mellitus and clinically-ascertained coronary artery disease and did not take lipid- lowering or antihypertensive drugs.

Only 0.7 and 1.3% of the variance in leisure time physical activity in women and men, respec- tively, was explained by the amount of TV watching. Leisure time physical activity had a clearly favorable, and TV

[page3image14824]

watching an unfavorable association with anthropometric measurements (BMI (body mass index), waist girth, waist-hip ratio, subscapular and triceps skinfold thickness). The odds ratio (95% CI) of being overweight was 0.41 (0.28-0.62) in women and 0.69 (0.46-1.04) in men in the highest quartile of leisure time physical activity compared to the lowest quartile. The odds ratio increased for increasing quartiles of TV watching to 2.12 (1.45-3.10) in women and 1.61 (1.07-2.43) in men.

Watching TV only 1 h per day in women with a BMI of 30 kg/m2 and doing about 75 min of mod- erate exercise per week was associated with a BMI 1.8 kg/m2 lower than in women watching TV 3 h per day and doing the same amount of exercise. Those with twice the amount of moderate exercise and watching TV 1 h per day had a BMI 0.45 kg/m2 lower.

Furthermore, leisure time physical activity was negatively associated with concentrations of triglycerides and positively with HDL cholesterol in both genders.

TV watching was significantly positively associated with triglycerides and slightly negatively with HDL cholesterol in men. The observed associations of leisure time physical activity and TV watching with atherosclerosis risk factors were independent from each other, we analyzed the relation between leisure time physical activity, TV watching and the degree of IMT of the carotid arteries. Neither of these two measures was significantly associated with IMT.

In summary, TV watching, in addition to leisure time physical activity, shows an independent association with obesity-related anthropometric measurements, HDL and triglycerides. Decreasing the amount of TV watching might be effective as a first step in reducing atherosclerosis risk factors, especially overweight. PMID: 11164433 http:// www.ncbi.nlm.nih.gov/pubmed/11164433?dopt=AbstractPlus&hold- ing=f1000,f1000m,isrctn

[page4image15464] [page4image15624]

Balance

A pilot study of Wii Fit exergames to improve balance in older adults.

J Geriatr Phys Ther. 2011 Oct-Dec;34(4):161-7. doi: 10.1519/JPT. 0b013e3182191d98.Agmon M, Perry CK, Phelan E, Demiris G, Nguyen HQ.

Source: University of Washington, Seattle, WA 98195, USA.

Abstract

PURPOSE:

To determine the safety and feasibility of using Nintendo Wii Fit exergames to improve balance in older adults.

METHODS:

Seven older adults aged 84 (5) years with impaired balance (Berg Balance Scale [BBS] score < 52 points) were recruited from 4 continuing care retirement communities to participate in a single group pre- and postevaluation of Wii Fit exergames. Participants received individualized instructions (at least 5 home visits) on playing 4 exergames (basic step, soccer heading, ski slalom, and table tilt) and were asked to play these games in their homes at least 30 minutes 3 times per week for 3 months and received weekly telephone follow-up. They also completed a paper log of their exergame play and rated their enjoyment immediately after each session. Participants completed the BBS, 4-Meter Timed Walk test, and the Physical Activity Enjoyment Scale at baseline and 3 months. Semistructured interviews were conducted at the 3-month evaluation.

RESULTS:

Participants safely and independently played a mean of 50 sessions, median session duration of 31 minutes. Two of the games were modified to ensure participants' safety. Participants rated high enjoyment immediately after exergame play and expressed experiencing improved balance with daily activities and desire to play exergames with their grandchildren. Berg Balance Scores increased from 49 (2.1) to 53 (1.8)

[page5image15352]

points (P = .017). Walking speed increased from 1.04 (0.2) to 1.33 (0.84) m/s (P = .018).

CONCLUSIONS:

Use of Wii Fit for limited supervised balance training in the home was

safe and feasible for a selected sample of older adults. Further research is needed to determine clinical efficacy in a larger, diverse sample and

ascertain whether Wii Fit exergames can be integrated into physical therapy practice to promote health in older adults.

PMID: 22124415

The effect of the Nintendo Wii Fit and exercise in improving balance and quality of life in community dwelling elders, Technol Health Care. 2012;20(2):95-115. doi: 10.3233/THC-2011-0661.

Franco JR, Jacobs K, Inzerillo C, Kluzik J. Source: Boston University, Haskell, NJ, USA.

Abstract

INTRODUCTION:

This study compared the effect of Nintendo Wii Fit to the Matter of Balance program, a valid and reliable program, on improving balance, and well-being to decrease the risk of falls.

METHODS:

Residents of an independent living senior housing facility were recruited and thirty-two residents ages 63 to 90 participated. Participants were separated into three groups: (1) Wii Fit group (n=11) completed balance games on the Wii Fit in individual sessions twice a week and supplemental home exercises; (2) Matter of Balance Group (n=11) completed exercises from the Matter of Balance Program in a group setting twice a week; (3) Control group (n=10) received no intervention. Intervention lasted three weeks.

RESULTS/FINDINGS:

One-way ANOVA's were completed. Scores from the assessments were not statistically significant at post-test Berg Balance Scale (p=0.837); Tinetti Gait and Balance Assessment (p=0.913); SF-36 (p=0.256). Results from a self-report demonstrated that Wii Fit is an enjoyable form of exercise for an elderly population.

CONCLUSION:

[page6image16816] [page6image16976] [page6image17136] [page6image17296] [page6image17456] [page6image17616]

Although, the interventions failed to significantly increase balance, with an increase in intervention duration of Wii Fit or Matter of Balance balance may be improved. Although results were not significant this study adds to the growing body of evidence regarding the use of Wii Fit as a rehabilitation tool.

© 2012 – IOS Press and the authors. All rights reserved

PMID: 22508022

Home-based balance training programme using Wii Fit with balance board for Parkinsons's disease: a pilot study.

Esculier JF, Vaudrin J, Bériault P, Gagnon K, Tremblay LE., J Rehabil Med. 2012 Feb;44(2):144-50. doi: 10.2340/16501977-0922.
Source: Faculty of Health Sciences, School of Rehabilitation, University of Ottawa, Québec, Canada.

Abstract

OBJECTIVES:

To evaluate the effects of a home-based balance training programme using visual feedback (Nintendo Wii Fit game with balance board) on balance and functional abilities in subjects with Parkinson's disease, and to compare the effects with a group of paired healthy subjects.

SUBJECTS:

Ten subjects with moderate Parkinson's disease and 8 healthy elderly subjects.

METHODS:

Subjects participated in a 6-week home-based balance training programme using Nintendo Wii Fit and balance board. Baseline measures were taken before training for the Sit-to-Stand test (STST), Timed-Up-and-Go (TUG), Tinetti Performance Oriented Mobility Assessment (POMA), 10-m walk test, Community Balance and Mobility assessment (CBM), Activities-specific Balance and Confidence scale (ABC), unipodal stance duration, and a force platform. All measurements were taken again after 3 and 6 weeks of training.

RESULTS:

The Parkinson's disease group significantly improved their results in TUG, STST, unipodal stance, 10-m walk test, CBM, POMA and force platform at the end of the 6- week training programme. The healthy subjects group significantly improved in TUG, STST, unipodal stance and CBM. e Parkinson's disease group significantly improved their results in TUG, STST, unipodal stance, 10-m walk test, CBM, POMA and force

[page7image17800] [page7image17960] [page7image18120] [page7image18280] [page7image18440] [page7image18600]

platform at the end of the 6-week training programme. The healthy subjects group significantly improved in TUG, STST, unipodal stance and CBM.

CONCLUSION:

This pilot study suggests that a home-based balance programme using Wii Fit with balance board could improve static and dynamic balance, mobility and functional abilities of people affected by Parkinson's disease.

PMID: 22266676

.

Feasibility of Wii Fit training to improve clinical measures of balance in older adults. Clin Interv Aging. 2013;8:775-81. doi: 10.2147/ CIA.S46164. Epub 2013 Jun 24, Bieryla KA, Dold NM.

Source: Biomedical Engineering Department, Bucknell University, Lewisburg, PA 17837, USA.

Abstract

BACKGROUND AND PURPOSE:

Numerous interventions have been proposed to improve balance in older adults with varying degrees of success. A novel approach may be to use an off-the-shelf video game system utilizing real-time force feedback to train older adults. The purpose of this study is to investigate the feasibility of using Nintendo's Wii Fit for training to improve clinical measures of balance in older adults and to retain the improvements after a period of time.

METHODS:

Twelve healthy older adults (aged >70 years) were randomly divided into two groups. The experimental group completed training using Nintendo's Wii Fit game three times a week for 3 weeks while the control group continued with normal activities. Four clinical measures of balance were assessed before training, 1 week after training, and 1 month after training: Berg Balance Scale (BBS), Fullerton Advanced Balance (FAB) scale, Functional Reach (FR), and Timed Up and Go (TUG). Friedman two-way analysis of variance by ranks was conducted on the control and experimental group to determine if training using the Wii Balance Board with Wii Fit had an influence on clinical measures of balance.

RESULTS:

Nine older adults completed the study (experimental group n = 4, control group n = 5). The experimental group significantly increased their BBS after training while the control group did not. There was no significant change for either group with FAB, FR, and TUG.

CONCLUSION:

[page8image19176]

Balance training with Nintendo's Wii Fit may be a novel way for older adults to improve balance as measured by the BBS.

PMID: 23836967

Wii-fit for improving gait and balance in an assisted living facility: a pilot study. J Aging Res. 2012;2012:597573. doi: 10.1155/2012/597573. Epub 2012 Jun 13.

Padala KP, Padala PR, Malloy TR, Geske JA, Dubbert PM, Dennis RA, Garner KK, Bopp MM, Burke WJ, Sullivan DH.
Source: Reynolds Department of Geriatrics, University of Arkansas for Medical Sciences, Little Rock, AR, USA.

Abstract

Objectives. To determine the effects on balance and gait of a Wii-Fit program compared to a walking program in subjects with mild Alzheimer's dementia (AD).

Methods. A prospective randomized (1 : 1) pilot study with two intervention arms was conducted in an assisted living facility with twenty-two mild AD subjects. In both groups the intervention occurred under supervision for 30 minutes daily, five times a week for eight weeks. Repeated measures ANOVA and paired t-tests were used to analyze changes.

Results. Both groups showed improvement in Berg Balance Scale (BBS), Tinetti Test (TT) and Timed Up and Go (TUG) over 8 weeks. However, there was no statistically significant difference between the groups over time. Intragroup analysis in the Wii-Fit group showed significant improvement on BBS (P = 0.003), and TT (P = 0.013). The walking group showed a trend towards improvement on BBS (P = 0.06) and TUG (P = 0.07) and significant improvement in TT (P = 0.06).

Conclusion. This pilot study demonstrates the safety and efficacy of Wii-Fit in an assisted living facility in subjects with mild AD. Use of Wii-Fit resulted in significant improvements in balance and gait comparable to those in the robust monitored walking program. These results need to be confirmed in a larger, methodologically sound study.

PMID: 22745909

Body Mass Index

Joint associations of physical activity and sedentary behaviors with body mass index: results from a time use survey of US adults.

[page9image18200] [page9image18360] [page9image18520] [page9image18680] [page9image18840] [page9image19000] [page9image19160] [page9image19320] [page9image19480] [page9image19640] [page9image19800] [page9image19960] [page9image20120]

Int J Obes (Lond). 2009 Dec;33(12):1427-36.
Dunton GF, Berrigan D, Ballard-Barbash R, Graubard B, Atienza AA. Source
Health Promotion Research Branch, Behavioral Research Program, Division of Cancer Control and Population Sciences, National Cancer Institute, Bethesda, MD, USA. dunton@usc.edu Abstract
OBJECTIVE:
Obesity risk is negatively associated with physical activity and positively associated with time spent in sedentary behaviors. Yet, it is not known how different combinations of sedentary and active behavior are associated with body mass index (BMI). This study examined the interaction between time spent in physical activity and sedentary behavior on BMI in US adults.
DESIGN:

Cross-sectional, data from the 2006 American Time Use Survey. SUBJECTS:
10 984 non-underweight adults (aged 21 + years). MEASUREMENT:

A phone interview assessed all activities performed in the past 24 h, height, weight, health status, and other sociodemographic characteristics. Time spent in (1) moderate-to-vigorous leisure-time physical activity (MVPA), (2) active transportation (walking, biking), (3) sedentary leisure activi- ties (TV/movie watching, computer use, playing games, reading), and (4) sedentary transportation (motorized vehicles) was determined from activity coding. BMI was calculated.

RESULTS:
After adjusting for age, gender, education level, race/ethnicity, and health status, sample-weighted linear regressions found significant interactions for leisure MVPA x TV/movies, leisure MVPA x playing games, active transportation x sedentary transportation, and active transportation x read- ing (Ps<0.0001). For example, the group of adults watching <60 min per day of TV/movies and engaging in > or =60 min per day of leisure MVPA had lower average BMI compared to the group

[page10image14472]

watching <60 min per day of TV/movies and reporting <60 min per day of leisure MVPA (P<0.0001). In contrast, for adults watching > or =189 min per day of TV/movies, there was not a significant difference in BMI by time spent in leisure MVPA.

CONCLUSION:
Data from a US time use survey indicate that the strength of the association between certain types of sedentary behavior and BMI varies according to time spent in certain types of physical activity and vice versa.
PMID: 19806160

Joint associations of physical activity and sedentary behaviors with body mass index: results from a time use survey of US adults.

Dunton GF, Berrigan D, Ballard-Barbash R, Graubard B, Atienza AA., Int J Obes (Lond). 2009 Dec;33(12):1427-36.
Source
Health Promotion Research Branch, Behavioral Research Program, Division of Cancer Control and Population Sciences, National Cancer Institute, Bethesda, MD, USA.

OBJECTIVE:
Obesity risk is negatively associated with physical activity and positively associated with time spent in sedentary behaviors. Yet, it is not known how different combinations of sedentary and active behavior are associated with body mass index (BMI). This study examined the interaction between time spent in physical activity and sedentary behavior on BMI in US adults.
DESIGN:
Cross-sectional, data from the 2006 American Time Use Survey. SUBJECTS:
10 984 non-underweight adults (aged 21 + years).
MEASUREMENT:
A phone interview assessed all activities performed in the past 24 h, height, weight, health status, and other sociodemographic characteristics.

Time spent in (1) moderate-to-vigorous leisure-time physical activity (MVPA), (2) active transportation (walking, biking), (3) sedentary leisure activi- ties (TV/movie watching, computer use, playing games, reading), and (4) sedentary transportation (motorized vehicles) was determined from activity coding. BMI was calculated.

RESULTS:
After adjusting for age, gender, education level, race/ethnicity, and health status, sample-weighted linear regressions found significant interactions for leisure MVPA x TV/movies, leisure MVPA x playing games, active transportation x sedentary transportation, and active transportation x read- ing (Ps<0.0001). For example, the group of adults watching <60 min per day of TV/movies and engaging in > or =60 min per day of leisure MVPA had lower average BMI compared to the group watching <60 min per day of TV/movies and reporting <60 min per day of leisure MVPA (P<0.0001). In contrast, for adults watching > or =189 min per day of TV/movies, there was not a significant difference in BMI by time spent in leisure MVPA.
CONCLUSION:
Data from a US time use survey indicate that the strength of the association between certain types of sedentary behavior and BMI varies according to time spent in certain types of physical activity and vice versa.
PMID: 19806160

Scand J Med Sci Sports. 2008 Jun;18(3):309-17. Epub 2007 Jul 23. Changes in physical activity behavior and the development of body mass index during the last 30 years in Norway.
Anderssen SA, Engeland A, Søgaard AJ, Nystad W, Graff-Iversen S, Holme I.
Source
Department of Sports Medicine, Norwegian School of Sports Sciences, Oslo, Norway.
Abstract

Body mass index (BMI; kg/m(2)) has increased markedly in the last decades. We hypothesized that highly physically active persons both at work and at leisure would be resistant to weight gain. The hypothesis was tested by analyzing Norwegian cross-sectional data collected in the period 1972-2002. Participants were 214,449 men and 206,136 women (aged 20-70 years). During the last 30 years in men and the last 15 years in women, a systematic larger BMI increase per year was observed in the sedentary [regression coefficients (SE) in men 0.060 (0.004) kg/m(2) and women 0.137 (0.012) kg/m(2)] compared with highly physically active groups [regression coeffi- cients (SE) in men 0.036 (0.00 4) kg/ m(2), and in women -0.001 (0.039) kg/m(2)]. Analyses were robust to adjustments for age, smoking and education. There was a larger absolute net increase in the prevalence of obesity among the sedentary compared with persons performing light, moderate or heavy physical activity (PA) at leisure. PA level in women both at work and in leisure was not associated with weight gain during the last decades. This association was less evident among men. Men and women who were lightly, moderately or highly active at leisure were less likely to be obese compared with those who were sedentary.

PMID: 17645730

Breaks in sitting

Energy expenditure of interruptions to sedentary behavior.

Swartz AM, Squires L, Strath SJ. Int J Behav Nutr Phys Act. 2011 Jun 27;8:69. doi: 10.1186/1479-5868-8-69.
Source

Physical Activity and Health Research Laboratory, Department of Human Movement Sciences, University of Wisconsin-Milwaukee, Enderis Hall Room 453, PO Box 413, Milwaukee, WI 53201-0413, USA.

Abstract

BACKGROUND:
Advances in technology, social influences and environmental attributes have resulted in substan- tial portions of the day spent in sedentary pursuits. Sedentary behavior may be a cause of many chronic diseases including obesity, insulin resistance, type 2 diabetes and the metabolic syn- drome. Research demonstrated that breaking up sedentary time was beneficially associated with markers of body composition, cardiovascular health and type 2 diabetes. Therefore, the purpose of this study was to quantify the total energy expenditure of three different durations of physical activity within a 30-minute sedentary period and to examine the potential benefits of interrupting sedentary behavior with physical activity for weight control.
METHODS:
Participants completed four consecutive 30-minute bouts of sedentary behavior (reading, working on the computer, or doing other desk activities) with and without interruptions of walking at a self-selected pace. Bout one contained no walking interruptions. Bout two contained a 1-minute walking period. Bout three contained a 2-minute walking period. Bout four contained a 5-minute walking period. Body composition and resting metabolic rate were assessed.
RESULT:
Twenty males and females (18-39 years) completed this study. Results of the repeated measures analysis of variance with post-hoc testing showed that significantly more energy was expended during each 30 minute sedentary bout with a walking break than in the 30 minute sedentary bout (p < 0.05 for all comparisons). On average, participants expended an additional 3.0, 7.4, and 16.5 additional net or activity kilocalories during bouts 2, 3, and 4, respectively compared with bout 1. When extrapolated for a full eight-hour working day, this data shows that an individual would the- oretically expend an additional 24, 59 or 132 kilocalories per day, if they stood up and walked at anormal, self selected pace for one, two or five minutes every hour, respectively, compared with sit- ting for the 8-hour period.
CONCLUSIONS:

This study demonstrated that making small changes, such as taking a five minute walking break every hour could yield beneficial weight control or weight loss results. Therefore, taking breaks from sedentary time is a potential outlet to prevent obesity and the rise of obesity in developed countries. PMID: 21708007

Breaking up prolonged sitting reduces resting blood pressure in overweight/obese adults. Nutr Metab Cardiovasc Dis. 2014 Sep;24(9):

976-82. doi: 10.1016/j.numecd.2014.04.011. Epub 2014 May 2.

Larsen RN1, Kingwell BA2, Sethi P3, Cerin E4, Owen N5, Dunstan DW6.

Abstract

AIM:

To compare the effect of 7 h of prolonged sitting on resting blood pressure with a similar duration of sitting combined with intermittent brief bouts of light-intensity or moderate-intensity physical activity.

METHODS AND RESULTS:

Overweight/obese adults (n = 19; aged 45-65 years) were recruited for a randomized three-treatment crossover trial with a one-week washout between treatments: 1) uninterrupted sitting; 2) sitting with 2 min bouts of light-intensity walking at 3.2 km/h every 20 min; and, 3) sitting with 2 min bouts of moderate- intensity walking at between 5.8 and 6.4 km/h every 20 min. After an initial 2 h period seated, participants consumed a test meal (75 g carbohydrate, 50 g fat) and completed each condition over the next 5 h. Resting blood pressure was assessed oscillometrically every hour as a single measurement, 5 min prior to each activity bout. GEE models were adjusted for sex, age, BMI, fasting blood pressure and treatment order. After adjustment for potential confounding variables, breaking up prolonged sitting with light and moderate-intensity activity breaks was associated with lower systolic blood pressure [light: 120 ± 1 mmHg (estimated marginal mean ± SEM), P = 0.002; moderate: 121 ± 1 mmHg, P = 0.02], compared to uninterrupted sitting (123 ± 1 mmHg). Diastolic blood pressure was also significantly lower during both of the activity conditions (light: 76 ± 1 mmHg, P = 0.006; moderate: 77 ± 1 mmHg, P = 0.03) compared to uninterrupted sitting (79 ± 1 mmHg). No significant between-condition differences were observed in mean arterial pressure or heart rate.

[page15image18952] [page15image19112] [page15image19272] [page15image19432] [page15image19592] [page15image19752] [page15image19912] [page15image20072]

CONCLUSION:

Regularly breaking up prolonged sitting may reduce systolic and diastolic blood pressure.

PMID: 24875670

Business

Prolonged sedentary time and physical activity in workplace and non-work contexts: a cross-sectional study of office, customer service and call centre employees.

Int J Behav Nutr Phys Act. 2012 Oct 26;9:128. doi: 10.1186/1479-5868-9-128.
Thorp AA, Healy GN, Winkler E, Clark BK, Gardiner PA, Owen N, Dunstan DW.
Source
Baker IDI Heart and Diabetes Institute, Level 4 The Alfred Centre, 99 Commercial Road, Mel- bourne, Victoria 3004, Australia.

Abstract
BACKGROUND:
To examine sedentary time, prolonged sedentary bouts and physical activity in Australian employ- ees from different workplace settings, within work and non-work contexts.
METHODS:
A convenience sample of 193 employees working in offices (131), call centres (36) and customer service (26) was recruited. Actigraph GT1M accelerometers were used to derive percentages of time spent sedentary (<100 counts per minute; cpm), in prolonged sedentary bouts (≥20 minutes or ≥30 minutes), light-intensity activity (100-1951 cpm) and moderate-to-vigorous physical activ- ity (MVPA; ≥1952 cpm). Using mixed models adjusted for confounders, these were compared for: work days versus non-work days; work hours versus non-work hours (work days only); and, across workplace settings.

RESULTS:
Working hours were mostly spent sedentary (77.0%, 95%CI: 76.3, 77.6), with approximately half of this time accumulated in prolonged bouts of 20 minutes or more. There were significant (p<0.05) differences in all outcomes between workdays and non-work days, and, on workdays, between work- versus non-work hours. Results consistently showed "work" was more sedentary and had less light-intensity activity, than "non-work". The period immediately after work appeared important for MVPA. There were significant (p<0.05) differences in all sedentary and activity outcomes occurring during work hours across the workplace settings. Call-centre workers were generally the most sedentary and least physically active at work; customer service workers were typically the least sedentary and the most active at work.
CONCLUSION:
The workplace is a key setting for prolonged sedentary time, especially for some occupational groups, and the potential health risk burden attached requires investigation. Future workplace reg- ulations and health promotion initiatives for sedentary occupations to reduce prolonged sitting time should be considered.
PMID: 23101767

Stand-Sit Device Use

Reducing Occupational Sitting Time and Improving Worker Health: The Take-a-Stand Project, 2011.

Prev Chronic Dis. 2012 Oct;9:E154. doi: 10.5888.pcd9.110323. Pronk NP, Katz AS, Lowry M, Payfer JR.
Journey Well, HealthPartners, Mail Stop 21111H, PO Box 1309, 8170 33rd Ave South, Minneapolis, MN 55440-1309. E-mail: Nico.p.pronk@healthpartners.com.

BACKGROUND:
Prolonged sitting time is a health risk. We describe a practice-based study designed to reduce pro- longed sitting time and improve selected health factors among workers with sedentary jobs. COMMUNITY

[page17image14264]

CONTEXT:
We conducted our study during March??"May 2011 in Minneapolis, Minnesota, among employees with sedentary jobs.
METHODS:
Project implementation occurred over 7 weeks with a baseline period of 1 week (period 1), an intervention period of 4 weeks (period 2), and a postintervention period of 2 weeks (period 3). The intervention group (n = 24) received a sit-stand device during period 2 designed to fit their workstation, and the comparison group (n = 10) did not. We used experience-sampling methods to monitor sitting behavior at work during the 7 weeks of the project. We estimated change scores in sitting time, health risk factors, mood states, and several office behaviors on the basis of survey responses.
OUTCOME:
The Take-a-Stand Project reduced time spent sitting by 224% (66 minutes per day), reduced upper back and neck pain by 54%, and improved mood states. Furthermore, the removal of the device largely negated all observed improvements within 2 weeks. INTERPRETATION:
Our findings suggest that using a sit-stand device at work can reduce sitting time and generate other health benefits for workers.
PMID: 23057991

'Sedentary behaviour counselling' the next step in lifestyle counselling in primary care; pilot findings from the Rapid Assessment Disuse Index (RADI) study.
Br J Sports Med. 2012 Sep 13. [Epub ahead of print]

Shuval K, Dipietro L, Skinner CS, Barlow CE, Morrow J, Goldsteen R, Kohl HW 3rd.

Source
Division of Epidemiology, Human Genetics and Environmental Sciences, University of Texas, School of Public Health, Dallas and

Austin, Texas, USA. Abstract

BACKGROUND:
Accumulating evidence emphasises a relationship between prolonged sitting and increased risk for cardiometabolic disorders and premature death irrespective of the protective effects of physi- cal activity. Primary care physicians have the potential to play a key role in modifying patients' sedentary behaviour alongside physical activity.
METHODS:
A pilot study examining sedentary behaviour and physical activity counselling in a primary care clinic. A total of 157 patients completed a detailed survey related to lifestyle counselling received from their primary care physician. We analysed these responses to describe counselling practices within the 5A framework, and to examine correlates (ie, patients' demographics, sedentary behav- iour and physical activity and clinical variables) related to receiving counselling. RESULTS:
A total of 10% received general advice to decrease sitting time, in comparison with 53% receiving general physical activity counselling. None, however, received a written plan pertaining to seden- tary behaviour whereas 14% received a written physical activity prescription. Only 2% were pro- vided with specific strategies for sedentary behaviour change in comparison with 10% for physical activity change. Multivariable analysis revealed that patients who were obese were more likely to receive counselling to decrease sitting (OR=7.0; 95% CI 1.4 to 35.2). In comparison, higher odds for receiving physical activity counselling were associated with being younger, aged 40-59 years (OR=2.4; 95% CI 1.1 to 5.4); and being a non-smoker (OR=6.1; 95% CI 1.3 to 28.4). CONCLUSIONS:
This study is the first to assess sedentary behaviour counselling practices in primary care and such practices appear to be infrequent. Future research should attempt to establish a 'knowledge base' to inform development of sedentary behaviour interventions, which should be

followed by testing feasibility, efficacy, and subsequent effectiveness of these programmes in a clinical setting. PMID: 22976910

Foot Swelling in VDT Operators with Sitting and Sit-Stand Workstations 1.Rajendra D. Paul11.1Technologies and Concepts Group Haworth, Inc. Holland, Michigan Abstract

In a controlled field study, effect of sit-stand workstations on foot swelling during the course of a workday was monitored in visual display terminal (VDT) operators. Six VDT operators first worked in offices furnished with nonadjustable sitting workstations. Then they worked in offices furnished with sit-stand adjustable furniture for six weeks. In the later setting, they stood for 15 minutes every hour. In both settings, the foot swelling was measured at 8 a.m., 12 p.m., 1 p.m. and 5 p.m. using a foot volumeter. Between 12 p.m. and 1 p.m., subjects walked for 20 minutes and sat for 40 minutes. The results showed that the average right foot swelling in offices with sit-stand adjustable furniture was significantly less than that in offices with nonadjustable furniture, 12.3 ml (1.1 percent) compared to 21 ml (1.8 percent). These results suggest that activity promoted using sit-stand workstations benefits sedentary office workers.

Several hypotheses have been proposed for the pathogenesis of work- related musculoskeletal symptoms and pain [27 – 31]. One suggests that low static contrace tion during work may result in a recruiting pattern orf motor programme, in which only type I muscle fibres are used, and this may lead to selective motor unit fatigue and damage [32]. A similar hypothesis known as the ‘Cin- derella hypothesis’ has been proposed by Hagg [28]m In line with these hypotheses is the over- load of type I muscle fibres during prolonged static contractions. The theor y about an overload of type I muscle fibres has been suppor ted in morphological studies in which ragged-red fibres (injured type I muscle fibres) were observed to be associated with occupational static loads [33,34]

The results from a prospective study by Ariens et al. showed a positive association between sitting at work for more than 95% of the working time and neck pain; trend was also obser ved for a pos- itive relation between neck flexion and neck pain.

: (http://occmed.oxfordjournals.org/content/55/3/168.full.pdf

Reminder software on computer helps reduce sitting time

Point-of-choice prompts to reduce sitting time at work: a randomized trial. •Am J Prev Med. 2012 Sep;43(3):293-7. doi: 10.1016/j.amepre.2012.05.010. Evans RE, Fawole HO, Sheriff SA, Dall PM, Grant PM, Ryan CG.
Source

School of Health and Life Sciences, Glasgow Caledonian University, Glasgow, United Kingdom. Abstract
BACKGROUND:
Prolonged sitting is prevalent in the workplace and is associated with adverse health markers. PURPOSE:

Investigate the effects of point-of-choice (PoC) prompting software, on the computer used at work (PC), to reduce long uninterrupted sedentary periods and total sedentary time at work.
DESIGN:

Assessor-blinded, parallel group, active-controlled randomized trial. SETTING/PARTICIPANTS:

A convenience sample of office workers from Glasgow, United Kingdom. Data were collected April to June 2010, and analyzed October 2010 to June 2011.
INTERVENTION:

The education group (n=14) received a brief education session on the importance of reducing long sitting periods at work. The PoC group (n=14) received the same education along with prompting software on their PC for 5 workdays, which reminded them to stand up every 30

[page21image13704]

minutes.
MAIN OUTCOME MEASURES:

Sitting time was measured objectively using the activPALTM activity monitor for 5 workdays at baseline and 5 workdays during the intervention. The number and time spent sitting in events >30 minutes' duration were the main outcome measures.

RESULTS:

At baseline, participants spent 5.7±1.0 hours/day (76%±9%) of their time at work sitting. Of that time, 3.3±1.3 hours/day was spent sitting in 3.7±1.4 events >30 minutes. There was a significant difference between the groups in the change (intervention to baseline) of both the number (ANCOVA; -6.8%, p=0.014) and duration (-15.5%, p=0.007) of sitting events >30 minutes. Dur- ing the intervention, compared with baseline, the PoC group reduced the number (paired t-test; - 0.11 events/hour, p=0.045) and duration (-12.2%, p=0.035) of sitting events >30 minutes. How- ever, there was no significant difference in total sitting time between groups (-4.4%, p=0.084). CONCLUSIONS:

Point-of-choice prompting software on work computers recommending taking a break from sit- ting plus education is superior to education alone in reducing long uninterrupted sedentary peri- ods at work. TRIAL REGISTRATION:

This trial was registered at ClinicalTrials.govNCT01628861.
Copyright © 2012 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.
PMID: 22898122

Reducing sitting time in office workers: Short-term efficacy of a multicomponent intervention.

Prev Med. 2013 Apr 15. pii: S0091-7435(13)00113-8. doi: 10.1016/ j.ypmed.2013.04.004. [Epub ahead of print]

Healy GN, Eakin EG, Lamontagne AD, Owen N, Winkler EA, Wiesner G, Gunning L, Neuhaus M, Lawler S, Fjeldsoe BS, Dunstan DW.

Source
The University of Queensland, School of Population Health, Brisbane, Australia; Baker IDI Heart and Diabetes Institute, Melbourne, Australia. Electronic address: g.healy@uq.edu.au.
Abstract
OBJECTIVE:
To investigate the short-term efficacy of a multicomponent intervention to reduce office workers' sitting time.
METHODS:
Allocation for this non-randomized controlled trial (n=43 participants; 56% women; 26-62years; Melbourne, Australia) was by office floor, with data collected during July-September 2011. The 4- week intervention emphasized three key messages: "Stand Up, Sit Less, Move More" and com- prised organizational, environmental, and individual elements. Changes in minutes/day at the

workplace spent sitting (primary outcome), in prolonged sitting (sitting time accumulated in bouts ≥30min), standing, and moving were objectively measured (activPAL3).
RESULTS:

Relative to the controls, the intervention group significantly reduced workplace sitting time (mean change [95%CI]: -125 [-161, -89] min/8-h workday), with changes primarily driven by a reduction in prolonged sitting time (-73 [-108, -40] min/8-h workday). Workplace sitting was almost exclusively replaced by standing (+127 [+92, +162] min/8-h workday) with non-significant changes to stepping time (-2 [-7, +4] min/ 8-h workday) and number of steps (-70 [-350, 210]).

CONCLUSIONS:

This multicomponent workplace intervention demonstrated that substantial reductions in sitting time are achievable in an office setting.

[page23image13432]

Larger studies with longer timeframes are needed to assess sustainability of these changes, as well as their potential longer-term impacts on health and work-related outcomes.

PMID: 23597658

Sit-stand workstations: a pilot intervention to reduce office sitting time.

Am J Prev Med. 2012 Sep;43(3):298-303. doi: 10.1016/j.amepre. 2012.05.027. Alkhajah TA, Reeves MM, Eakin EG, Winkler EA, Owen N, Healy GN. Source
University of Queensland, School of Population Health, Queensland, Australia. Abstract

BACKGROUND:
Sitting time is a prevalent health risk among office-based workers. PURPOSE:
To examine, using a pilot study, the efficacy of an intervention to reduce office workers' sitting time.
DESIGN:
Quasi-experimental design with intervention-group participants recruited from a single workplace that was physically separate from the workplaces of comparison-group participants. SETTING/ PARTICIPANTS:
Office workers (Intervention, n=18; Comparison, n=14) aged 20-65 years from Brisbane, Austra- lia; data were collected and analyzed in 2011.
INTERVENTION:
Installation of a commercially available sit-stand workstation.
MAIN OUTCOME MEASURES:
Changes from baseline at 1-week and 3-month follow-up in time spent sitting, standing, and step- ping at the workplace and during all waking time (activPAL3 activity monitor, 7-day observation). Fasting total cholesterol, high-density lipoprotein (HDL) cholesterol, triglycerides,

and glucose levels were assessed at baseline and 3 months (Cholestech LDX Analyzer). Acceptability was assessed with a 5-point response scale (eight items).
RESULTS:

The intervention group (relative to the comparison group) reduced sitting time at 1-week follow- up by 143 minutes/day at the workplace (95% CI= -184, -102) and 97 minutes/day during all wak- ing time (95% CI= -144, -50). These effects were maintained at 3 months (-137 minutes/day and - 78 minutes/day, respectively). Sitting was almost exclusively replaced by standing, with minimal

changes to stepping time. Relative to the comparison group, the intervention group increased HDL cholesterol by an average of 0.26 mmol/L (95% CI=0.10, 0.42). Other biomarker differ- ences were not significant. There was strong acceptability and preference for using the worksta- tions, though some design limitations were noted.

CONCLUSIONS:
This trial is the first with objective measurement and a comparison group to demonstrate that the introduction of a sit-stand workstation can substantially reduce office workers' sitting time both at the workplace and overall throughout the week.
Copyright © 2012 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.
PMID: 22898123

Treadmill workstations: a worksite physical activity intervention in overweight and obese office workers.

J Phys Act Health. 2011 Nov;8(8):1034-43.
John D, Thompson DL, Raynor H, Bielak K, Rider B, Bassett DR. Source
Dept of Kinesiology, University of Massachusetts, Amherst, MA, USA. Abstract
PURPOSE:

To determine if a treadmill-workstation (TMWS) increases physical activity (PA) and influences anthropometric, body composition, cardiovascular, and metabolic variables in overweight and obese office- workers.

METHODS:
Twelve (mean age= 46.2 ± 9.2 years) overweight/obese sedentary office- workers (mean BMI= 33.9 ± 5.0 kg·m-2) volunteered to participate in this 9-month study. After baseline measurements of postural allocation, steps per day, anthropometric variables, body composition, cardiovascular, and metabolic variables, TMWS were installed in the participants' offices for their use. Baseline measurements were repeated after 3 and 9 months. Comparisons of the outcome variables were made using repeated-measures ANOVAs or nonparametric Friedman's Rank Tests.
RESULTS:
Between baseline and 9 months, significant increases were seen in the median standing (146-203 min·day-1) and stepping time (52-90 min·day-1) and total steps/day (4351-7080 steps/day; P < .05). Correspondingly, the median time spent sitting/lying decreased (1238-1150 min·day-1; P < .05). Using the TMWS significantly reduced waist (by 5.5 cm) and hip circumference (by 4.8 cm), low-density lipoproteins (LDL) (by 16 mg·dL-1), and total cholesterol (by 15 mg·dL-1) during the study (P < .05).
CONCLUSION:
The additional PA energy expenditure from using the TMWS favorably influenced waist and hip circumferences and lipid and metabolic profiles in overweight and obese office-workers.
PMID: 22039122

Point-of-choice prompts to reduce sitting time at work: a randomized trial.

Am J Prev Med. 2012 Sep;43(3):293-7. doi: 10.1016/j.amepre. 2012.05.010. Evans RE, Fawole HO, Sheriff SA, Dall PM, Grant PM,

Ryan CG. Source

School of Health and Life Sciences, Glasgow Caledonian University, Glasgow, United Kingdom. Abstract
BACKGROUND:
Prolonged sitting is prevalent in the workplace and is associated with adverse health markers. PURPOSE:

Investigate the effects of point-of-choice (PoC) prompting software, on the computer used at work (PC), to reduce long uninterrupted sedentary periods and total sedentary time at work.
DESIGN:

Assessor-blinded, parallel group, active-controlled randomized trial. SETTING/PARTICIPANTS:

A convenience sample of office workers from Glasgow, United Kingdom. Data were collected April to June 2010, and analyzed October 2010 to June 2011.
INTERVENTION:
The education group (n=14) received a brief education session on the importance of reducing long sitting periods at work. The PoC group (n=14) received the same education along with prompting software on their PC for 5 workdays, which reminded them to stand up every 30 minutes.

MAIN OUTCOME MEASURES:
Sitting time was measured objectively using the activPALTM activity monitor for 5 workdays at baseline and 5 workdays during the intervention. The number and time spent sitting in events >30 minutes' duration were the main outcome measures.
RESULTS:
At baseline, participants spent 5.7±1.0 hours/day (76%±9%) of their time at work sitting. Of that time, 3.3±1.3 hours/day was spent sitting in 3.7±1.4 events >30 minutes. There was a significant difference between

the groups in the change (intervention to baseline) of both the number (ANCOVA; -6.8%, p=0.014) and duration (-15.5%, p=0.007) of sitting events >30 minutes. During the intervention, compared with baseline, the PoC group reduced the number (paired t-test; - 0.11 events/hour, p=0.045) and duration (-12.2%, p=0.035) of sitting events >30 minutes. How- ever, there was no significant difference in total sitting time between groups (-4.4%, p=0.084). CONCLUSIONS:

Point-of-choice prompting software on work computers recommending taking a break from sit- ting plus education is superior to education alone in reducing long uninterrupted sedentary peri- ods at work. TRIAL REGISTRATION:

This trial was registered at ClinicalTrials.govNCT01628861.
Copyright © 2012 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.
PMID: 22898122

Cancer

Don't take cancer sitting down: A new survivorship research agenda.

Cancer. 2013 Mar 15. doi: 10.1002/cncr.28028. [Epub ahead of print] Lynch BM, Dunstan DW, Vallance JK, Owen N.
Source
Physical Activity Laboratory, Baker IDI Heart and Diabetes Institute, Melbourne, Victoria, Aus- tralia; Melbourne School of Population Health, Faculty of Medicine, Dentistry and Health Sci- ences, The University of Melbourne, Melbourne, Victoria, Australia. brigid.lynch@bakeridi.edu.au.

Abstract
Cancer survival is associated with considerable physical and psychosocial burden. Broadly accessible, nonpharmacologic measures that may extend disease-free survival, limit comorbid disease, and enhance quality of life are required. Sedentary behavior (too much

[page28image13504]

sitting) is now under- stood to be a health risk that is additional to, and distinct from, the hazards of too little exerise. Of particular note, it is associated with adiposity, insulin resistance, and markers of inflammation. Therefore, it is plausible that sedentary behavior may contribute to adverse cancer outcomes (disease progression, recurrence, or death) and to the development of comor- bid chronic disease. Initial studies indicate that cancer survivors spend two-thirds of their waking hours sitting. Among colorectal cancer survivors, sedentary behavior may contribute to all- cause and disease-specific mortality, weight gain, comorbid cardiovascular disease, and diminished quality of life. There is a need for dose-response evidence, and for a broader under- standing of the underlying mechanisms by which prolonged sitting time may affect cancer survi- vors' health. Cancer 2013. © 2013 American Cancer Society.

Copyright © 2013 American Cancer Society. PMID: 23504979

Breast Cancer Research and Treatment [2011, 130(1):183-94]
Type: Journal Article, Research Support, Non-U.S. Gov't
DOI: 10.1007/s10549-011-1559-2
Physical activity reduces the risk of postmenopausal breast cancer through multiple inter-related biologic mechanisms; sedentary time may contribute additionally to this risk. We examined cross-sectional associations of objectively assessed physical activity and sedentary time with estab- lished biomarkers of breast cancer risk in a population-based sample of postmenopausal women. Accelerometer, anthropometric and laboratory data were available for 1,024 (n = 443 fasting) postmenopausal women in the U.S. National Health and Nutrition Examination Survey 2003- 2006. Associations of quartiles of the accelerometer variables (moderate- to vigorous-intensity activity, light- intensity activity and sedentary time per day; average length of active and sedentary bouts) with the continuous biomarkers were assessed using linear regression models. Following adjustment for potential confounders, including sedentary time, moderate- to vigorous- intensity

activity had significant (P < 0.05), inverse associations with all biomarker outcomes (body mass index, waist circumference, C-reactive protein, fasting plasma glucose, fasting insulin and homeostasis model assessment of insulin resistance). Light-intensity activity and sedentary time were significantly associated in fully adjusted models with all biomarkers except fasting glucose. Active bout length was associated with a smaller waist circumference and lower C-reactive protein levels, while sedentary bout length was associated with a higher BMI. The associations of objectively assessed moderate-to vigorous-intensity activity with breast cancer biomarkers are consistent with the established beneficial effects of self- reported exercise on breast cancer risk. Our findings further suggest that light-intensity activity may have a protective effect, and that sedentary time may independently contribute to breast can- cer risk. http://www.ukpubmedcentral.ac.uk/abstract/MED/21553294;jses- sionid=615961969565EFAC241B60197EA14E2E

Body esteem and mood among sedentary and active breast cancer survivors.

Pinto BM, Trunzo JJ. Mayo Clin Proc. 2004 Feb;79(2):181-6.
Source
Centers for Behavioral and Preventive Medicine, Miriam Hospital and Brown Medical School, Providence, RI 02903, USA. bpinto@lifespan.org

Abstract
OBJECTIVES:
To assess mood states and body esteem in 2 groups of breast cancer survivors, regular exercisers and sedentary women, and to examine these variables among younger and older women in each group.
PATIENTS AND METHODS:
Between 1998 and 2002, we conducted a cross-sectional study among early-stage breast cancer survivors at the Miriam Hospital in Providence, RI, comparing 40 women who reported regular exercise with 79

[page30image13800] [page30image13960]

sedentary women. We used multivariate and univariate analyses to compare the exercisers with sedentary women on fitness, physical activity, and questionnaire measures of body esteem and mood. Analyses were repeated after the 2 groups were subdivided by age (< 50 years vs > or = 50 years).

RESULTS:
Regular exercisers (mean +/- SD age, 54.57 +/- 9.18 years) reported significantly more positive attitudes toward their physical condition and sexual attractiveness; significantly less confusion, fatigue, depression, and total mood disturbance; and higher vigor than sedentary women (mean +/ - SD age, 52.33 +/- 9.11 years). Both younger and older exercisers had higher physical condition scores than their sedentary peers. Older exercisers reported higher vigor and less confusion, anger, fatigue, depression, and total mood disturbance than sedentary women, regardless of age. Younger exercisers reported higher vigor than their sedentary peers and less confusion than older sedentary women. CONCLUSIONS:
In this largely white sample of well-educated women, breast cancer survivors who exercised (par- ticularly older women) reported higher body esteem and better mood than sedentary breast cancer survivors. PMID: 14959912

Cardiovascular disease

Deleterious Associations of Sitting Time and Television Viewing Time With Cardiometabolic Risk Biomarkers

Australian Diabetes, Obesity and Lifestyle (AusDiab) study 2004–2005 1.Alicia A. Thorp, PHD1,2, Genevieve N. Healy, PHD1,2, Neville Owen, PHD1,2, Jo Salmon, PHD1,3, Kylie Ball, PHD3, Jonathan E. Shaw, MD1, Paul Z. Zimmet, MD1 and David W. Dun- stan, PHD1,2,3,4

Author Affiliations

1.1Baker IDI Heart and Diabetes Institute, Melbourne, Victoria, Australia;
2.2The University of Queensland, School of Population Health, Cancer Prevention Research Cen- tre, Brisbane, Australia;

3.3School of Exercise and Nutrition Sciences, Deakin University, Melbourne, Australia;
4.4Vario Health Institute, Edith Cowan University, Joondalup, Australia. 1.Corresponding author: Alicia Thorp

Abstract
OBJECTIVE We examined the associations of sitting time and television (TV) viewing time with continuously measured biomarkers of cardio-metabolic risk in Australian adults.
RESEARCH DESIGN AND METHODS Waist circumference, BMI, resting blood pressure, trig- lycerides, HDL cholesterol, fasting and 2-h postload plasma glucose, and fasting insulin were measured in 2,761 women and 2,103 men aged ≥30 years (mean age 54 years) without clinically diagnosed diabetes from the 2004–2005 Australian Diabetes, Obesity and Lifestyle (AusDiab) study. Multivariate linear regression analyses examined associations of self-reported sitting time and TV viewing time (hours per day) with these biomarkers, adjusting for potential confounding variables.
RESULTS For both women and men, sitting time was detrimentally associated with waist circum- ference, BMI, systolic blood pressure, fasting triglycerides, HDL cholesterol, 2-h postload plasma glucose, and fasting insulin (all P < 0.05), but not with fasting plasma glucose and diastolic blood pressure (men only). With the exception of HDL cholesterol and systolic blood pressure in women, the associations remained significant after further adjustment for waist circumference. TV viewing time was detrimentally associated with all metabolic measures in women and all except HDL cholesterol and blood pressure in men. Only fasting insulin and glucose (men only) remained deleteriously associated with TV viewing time after adjustment for waist circumference.

CONCLUSIONS In women and men, sitting time and TV viewing time were deleteriously asso- ciated with cardio-metabolic risk biomarkers, with sitting time having more consistent associa- tions in both sexes and being independent of central adiposity. Preventive initiatives aimed at reducing sitting time should focus on both nonleisure and leisure-time domains http://care.diabetesjournals.org/content/33/2/327.abstract

FULL TEXT http://care.diabetesjournals.org/content/33/2/327.full

Sedentary behaviors increase risk of cardiovascular disease mortality in men. Med Sci Sports Exerc. 2010 May;42(5):879-85. doi: 10.1249/MSS.0b013e3181c3aa7e.
Warren TY, Barry V, Hooker SP, Sui X, Church TS, Blair SN.

PURPOSE:

The purpose of this study was to examine the relationship between two sedentary behaviors (riding in a car and watching TV) and cardiovascular disease (CVD) mortality in men in the Aer- obics Center Longitudinal Study.

METHODS:
Participants were 7744 men (20-89 yr) initially free of CVD who returned a mail-back survey dur- ing 1982. Time spent watching TV and time spent riding in a car were reported. Mortality data were ascertained through the National Death Index until December 31, 2003. Cox regression anal- ysis quantified the association between sedentary behaviors (hours per week watching TV, hours per week riding in a car, and total hours per week in these two behaviors) and CVD mortality rates.
RESULTS:
Three hundred and seventy-seven CVD deaths occurred during 21 yr of follow-up. After age adjustment, time riding in a car and combined time spent in these two sedentary behaviors were positively (P(trend) < 0.001) associated with CVD death. Men who reported >10 h x wk(-1) riding in a car or >23 h x wk(-1) of combined sedentary behavior

[page33image15040] [page33image15200]

had 82% and 64% greater risk of dying from CVD than those who reported <4 or <11 h x wk(-1), respectively. The pat- tern of the association did not materially change after multivariate adjustment. Regardless of the amount of sedentary activity reported by these men, being older, having normal weight, being normotensive, and being physically active were associated with a reduced risk of CVD death. CONCLUSION:

In men, riding in a car and combined time spent in these two sedentary behaviors were significant CVD mortality predictors. In addition, high levels of physical activity were related to notably lower rates of CVD death even in the presence of high levels of sedentary behavior. Health pro- motion efforts targeting physically inactive men should emphasize both reducing sedentary activ- ity and increasing regular physical activity for optimal cardiovascular health.

PMID: 19996993

Effect of plantar micromechanical stimulation on cardiovascular responses to immobility.

Authors
Madhavan G, et al. Show all
Journal
Am J Phys Med Rehabil. 2005 May;84(5):338-45.
Affiliation
Clinical Sciences Research Center, Department of Bioengineering, Thomas J. Watson School of Engineering and Applied Science, State University of New York, Binghamton, New York, USA. Abstract
OBJECTIVE: We investigated the cardiovascular responses of adult women to the influence of extended quiet sitting and the extent to which these responses may be reversed by micromechani- cal stimulation of the plantar surface.
DESIGN: The cardiovascular responses of 20 healthy adult women (mean age, 55.9 +/- 4.45 yrs) were observed during quiet sitting with and without exposure to a plantar-based micromechanical stimulation. Beat-to-beat heart rate via electrocardiogram was acquired along with preexposure and postexposure blood pressures, from which heart rate variability and mean arterial pressure were determined. Seven stimulus frequencies (0, 15, 22, 44, 60, 90, and 120 Hz, all at 0.2 x g, peak to peak) were tested on each subject.
RESULTS: Over one-half of the women tested (11/20) exhibited a significant resting tachycardia (mean, 8.3 +/- 0.5 beats/min) with a corresponding decline in their systolic blood pressure (9.45 +/- 1.8 mm Hg) after 20 mins of quiet sitting. Plantar stimulation at 44 Hz (25 mum, peak to peak) was able to completely reverse the effect of immobility in this group, resulting in a heart rate decline of 2.5 beats/min (P < 0.0001) and a decrease of only 1 mm Hg in systolic pressure (P = 0.006).
CONCLUSION: We interpret these results to suggest that the immobility of quiet sitting has a profound effect on the cardiovascular systems in a large fraction of otherwise healthy women, perhaps due to inadequate muscle tone leading to venous insufficiency. Simple external stimulation of the plantar surface seems to be capable of preventing these cardiovascular stress-based responses.
PMID 15829780
http://www.ncbi.nlm.nih.gov/m/pubmed/15829780/

Cardiovascular systemic regulation by plantar surface stimulation.

[page35image16984]

Authors: Madhavan G, et al. Show all
Journal: Biomed Instrum Technol. 2006 Jan-Feb;40(1):78-84. Affiliation: Department of Orthopaedics, School of Medicine, Health Sciences Center, State Uni- versity of New York, Stony Brook, USA. guru@binghamton.edu
Abstract

The decreased blood pressure and flow rates associated with orthostasis have been implicated in the etiology of numerous clinical conditions, including deep vein thrombosis, chronic fatigue syn- drome, and more recently osteoporosis. Here, we investigate the potential of low- magnitude vibration, applied at the plantar surface, to inhibit the cardiovascular responses of adult women to the orthostatic stress associated with quiet sitting.

METHODS: Thirty healthy women, aged 22-82 years, were exposed to a plantar-based vibration immediately after taking a seated position. Seven stimulus frequencies (0, 15, 22, 44, 60, 90, and 120 Hz, all at 0.2g) were tested on each subject, and cardiovascular responses were followed for 20 minutes. Each subject experienced only a single test frequency on any day. Pre- and poststimu- lus blood pressures and continuous electrocardiogram results were obtained, from which mean arterial pressure (MAP) and heart rate variability (HRV) were calculated.

RESULTS: In the per-protocol study population (n = 25), 20 minutes of quiet sitting was associ- ated with an average depression of 8.95 mm Hg in systolic pressure and of 1.9 mm Hg in diastolic blood pressure, corresponding to an average decrease in MAP of 5.15 mm Hg. These orthostasis- based changes in blood pressure were significantly reduced by exposure to plantar vibration, in a frequency-dependent manner, with essentially complete suppression of the drop in MAP achieved with plantar stimulation at 44 Hz (P < or = . 01). In the orthostatically hypotensive subpopulation (n = 15), both the 9.3-mm Hg depression in MAP and the decline in HRV were eliminated by exposure to plantar vibrations in the 40- to 60-Hz range (P = .01 and P = .03, respectively).

[page36image16872]

These results are consistent with the hypothesis that the plantar vibration may be stimulating type IIA muscle fiber activity in the leg, which is critical for effective skeletal muscle pumping in the absence of locomotion.

CONCLUSIONS: Our findings lead us to suggest that noninvasive, low- level, plantar-based vibration in the regime of 30-60 Hz can significantly inhibit the effects of the orthostatic stress of quiet sitting on the cardiovascular system.

PMID 16544794

Cardiovascular systemic regulation by plantar surface stimulation. Biomed Instrum Technol. 2006 Jan-Feb;40(1):78-84.

Madhavan G, Stewart JM, McLeod KJ.
Source: Dpartment of Orthopaedics, School of Medicine, Health Sciences Center, State University of New York, Stony Brook, USA. guru@binghamton.edu

Abstract

The decreased blood pressure and flow rates associated with orthostasis have been implicated in the etiology of numerous clinical conditions, including deep vein thrombosis, chronic fatigue syndrome, and more recently osteoporosis. Here, we investigate the potential of low-magnitude vibration, applied at the plantar surface, to inhibit the cardiovascular responses of adult women to the orthostatic stress associated with quiet sitting.

METHODS:

Thirty healthy women, aged 22-82 years, were exposed to a plantar-based vibration immediately after taking a seated position. Seven stimulus frequencies (0, 15, 22, 44, 60, 90, and 120 Hz, all at 0.2g) were tested on each subject, and cardiovascular responses were followed for 20 minutes. Each subject experienced only a single test frequency on any day. Pre- and poststimulus blood pressures and continuous electrocardiogram results were obtained, from which mean arterial pressure (MAP) and heart rate variability (HRV) were calculated.

[page37image15088] [page37image15248] [page37image15408] [page37image15568] [page37image15728] [page37image15888]

RESULTS:

In the per-protocol study population (n = 25), 20 minutes of quiet sitting was associated with an average depression of 8.95 mm Hg in systolic pressure and of 1.9 mm Hg in diastolic blood pressure, corresponding to an average decrease in MAP of 5.15 mm Hg. These orthostasis-based changes in blood pressure were significantly reduced by exposure to plantar vibration, in a frequency-dependent manner, with essentially complete suppression of the drop in MAP achieved with plantar stimulation at 44 Hz (P < or = . 01). In the orthostatically hypotensive subpopulation (n = 15), both the 9.3-mm Hg depression in MAP and the decline in HRV were eliminated by exposure to plantar vibrations in the 40- to 60-Hz range (P = .01 and P = .03, respectively). These results are consistent with the hypothesis that the plantar vibration may be stimulating type IIA muscle fiber activity in the leg, which is critical for effective skeletal muscle pumping in the absence of locomotion.

CONCLUSIONS:

Our findings lead us to suggest that noninvasive, low-level, plantar-based vibration in the regime of 30-60 Hz can significantly inhibit the effects of the orthostatic stress of quiet sitting on the cardiovascular system.

.

Effect of plantar micromechanical stimulation on cardiovascular responses to immobility. Am J Phys Med Rehabil. 2005 May;84(5):338-45 Madhavan G, Stewart JM, McLeod KJ.
Source

Clinical Sciences Research Center, Department of Bioengineering, Thomas J. Watson School of Engineering and Applied Science, State University of New York, Binghamton, New York, USA.

Abstract

OBJECTIVE:

We investigated the cardiovascular responses of adult women to the influence of extended quiet sitting and the extent to which these responses may be reversed by micromechanical stimulation of the plantar surface.

[page38image16424]

DESIGN:

The cardiovascular responses of 20 healthy adult women (mean age, 55.9 +/- 4.45 yrs) were observed during quiet sitting with and without exposure to a plantar-based micromechanical stimulation. Beat-to-beat heart rate via electrocardiogram was acquired along with preexposure and postexposure blood pressures, from which heart rate variability and mean arterial pressure were determined. Seven stimulus frequencies (0, 15, 22, 44, 60, 90, and 120 Hz, all at 0.2 x g, peak to peak) were tested on each subject.

RESULTS:

Over one-half of the women tested (11/20) exhibited a significant resting tachycardia (mean, 8.3 +/- 0.5 beats/min) with a corresponding decline in their systolic blood pressure (9.45 +/- 1.8 mm Hg) after 20 mins of quiet sitting. Plantar stimulation at 44 Hz (25 mum, peak to peak) was able to completely reverse the effect of immobility in this group, resulting in a heart rate decline of 2.5 beats/min (P < 0.0001) and a decrease of only 1 mm Hg in systolic pressure (P = 0.006).

CONCLUSION:
We interpret these results to suggest that the immobility of quiet sitting has a profound effect on the cardiovascular systems in a large fraction of otherwise healthy women, perhaps due to inadequate muscle tone leading to venous insufficiency. Simple external stimulation of the plantar surface seems to be capable of preventing these cardiovascular stress-based responses.

PMID: 15829780

Sedentary Behaviour and Biomarkers of Cardiometabolic Health Risk in Adolescents: An Emerging Scientific and Public Health Issue

Rev Esp Cardiol.2010; 63 :261-4 - Vol.63 Núm 03 DOI: 10.1016/

S1885-5857(10)70057-8 Genevieve N. Healya y Neville Owena aCancer Prevention Research Centre, School of Population Health, The

University of Queen- sland, Brisbane, Australia. Baker IDI Heart and Diabetes Institute, Melbourne, Australia Artículo

A highlight of this issue of Revista Española de Cardiología is the report of original research by Martínez-Gómez et al,1 in which they examine the associations of objectively assessed sedentary time (too much sitting, as distinct from too little exercise) and body fatness with cardiovascular risk factors in a subsample of 201 adolescent participants of the Madrid AFINOS study. The key scientific features of their investigation are the objective measurement of ambulatory movement (and non-movement) using accelerometers, from which they derive the amount of time spent sed- entary. In their study, they conducted careful anthropometric measurements to determine central and overall adiposity, and measured a range of biomarkers of cardiovascular risk. They report sig- nificant associations of time spent sedentary and body fatness with biomarkers of cardiovascular risk in this group of young people aged 13 to 16 years.

Accelerometer-determined moderate intensity lifestyle activity and cardiometabolic health.

Camhi SM, Sisson SB, Johnson WD, Katzmarzyk PT, Tudor-Locke C. Prev Med. 2011 May 1;52(5):358-60. Epub 2011 Feb 16.
Source
Pennington Biomedical Research Center, 6400 Perkins Road, Baton Rouge, LA, USA. sarah.camhi@umb.edu

Abstract
OBJECTIVE:
Objective To assess the relationship between moderate intensity lifestyle activity (LA) and cardiometabolic health using accelerometer data from the National Health and Nutrition Examination Survey (NHANES) 2005-2006.
METHODS:
One thousand three hundred and seventy-one adults (50% men; 71% non-Hispanic white) pro- vided valid data to quantify time in LA [760-2019 counts per minute (CPM)] and moderate-to- vigorous physical activity (MVPA; ≥ 2020 CPM). Associations between LA [minutes per day (min/day); steps per day (steps/day)], and

[page40image14752]

cardiometabolic risk factors [triglycerides, HDL-cholesterol (HDL-C), blood pressure, glucose, waist circumference], metabolic syndrome, self- reported hypertension and diabetes were investigated using logistic regression. Analyses were adjusted for age, gender, race/ethnicity, and MVPA categories.

RESULTS:
Greater time in lifestyle activity LA (min/day), independent from moderate-to-vigorous physical activity MVPA, was associated with lower odds of elevated triglycerides (OR, 95% CI per 30 LA minutes: 0.89,0.83-0.97), low HDL-C (0.87,0.83-0.92), elevated waist circumference (0.88,0.83- 0.94), metabolic syndrome (0.87,0.80-0.96), and diabetes (0.67,0.55-0.82). The same cardiometa- bolic risk factors were also significantly associated with LA steps/day. No significant association was found between LA (min/day or steps/day) and glucose or blood pressure.
CONCLUSION:
Accumulation of time or steps in LA is independently related to lower odds for certain cardiomet- abolic risk factors. Research should consider the effects of increasing LA, which could influence future physical activity recommendations.
Copyright © 2011 Elsevier Inc. All rights reserved.
PMID: 21300082 [PubMed

Sedentary time in adults and the association with diabetes, cardiovascular disease and death: systematic review and meta- analysis.

Wilmot EG, Edwardson CL, Achana FA, Davies MJ, Gorely T, Gray LJ, Khunti K, Yates T, Bid- dle SJ.

Department of Cardiovascular Sciences, University of Leicester, Leicester Diabetes Centre, Leicester General Hospital, Gwendolen Road, Leicester, LE5 4PW, UK.

Diabetologia. 2012 Nov;55(11):2895-905. doi: 10.1007/ s00125-012-2677-z. Epub 2012 Aug 14. AIMS/HYPOTHESIS:

Sedentary (sitting) behaviours are ubiquitous in modern society. We conducted a systematic review and meta-analysis to examine the association of sedentary time with diabetes, cardiovascu- lar disease and cardiovascular and all-cause mortality.

METHODS:

Medline, Embase and the Cochrane Library databases were searched for terms related to seden- tary time and health outcomes. Cross-sectional and prospective studies were included. RR/HR and 95% CIs were extracted by two independent reviewers. Data were adjusted for baseline event rate and pooled using a random-effects model. Bayesian predictive effects and intervals were cal- culated to indicate the variance in outcomes that would be expected if new studies were conducted in the future.

RESULTS:

Eighteen studies (16 prospective, two cross-sectional) were included, with 794,577 participants. Fifteen of these studies were moderate to high quality. The greatest sedentary time compared with the lowest was associated with a 112% increase in the RR of diabetes (RR 2.12; 95% credible interval [CrI] 1.61, 2.78), a 147% increase in the RR of cardiovascular events (RR 2.47; 95% CI 1.44, 4.24), a 90% increase in the risk of cardiovascular mortality (HR 1.90; 95% CrI 1.36, 2.66) and a 49% increase in the risk of all-cause mortality (HR 1.49; 95% CrI 1.14, 2.03). The predictive effects and intervals were only significant for diabetes.

CONCLUSIONS/INTERPRETATION:

Sedentary time is associated with an increased risk of diabetes, cardiovascular disease and cardio- vascular and all-cause mortality; the

strength of the association is most consistent for diabetes. PMID: 22890825

Children and sitting

Television, reading, and computer time: correlates of school-day leisure-time sedentary behavior and relationship with overweight in children in the u.s.

Sisson SB, Broyles ST, Baker BL, Katzmarzyk PT., J Phys Act Health. 2011 Sep;8 Suppl 2:S188- 97.
Dept of Nutritional Sciences, University of Oklahoma Health Sciences Center, Oklahoma City, OK.

Abstract

BACKGROUND:
The purposes were 1) to determine if different leisure-time sedentary behaviors (LTSB), such as TV/video/video game viewing/playing (TV), reading for pleasure (reading), and nonschool com- puter usage, were associated with childhood overweight status, and 2) to assess the social- ecological correlates of LTSB.
METHODS:
The analytic sample was 33,117 (16,952 boys and 16,165 girls) participants from the 2003 National Survey of Children's Health. The cut-point for excessive TV and nonschool computer usage was ≥ 2 hr/ day. High quantities of daily reading for pleasure were classified as ≥ 31 min/ day. Weighted descriptive characteristics were calculated on the sample (means ± SE or fre- quency). Logistic regression models were used to determine if the LTSB were associated with overweight status and to examine social-ecological correlates.
RESULTS:
Over 35% of the sample was overweight. Odds of being overweight were higher in the 2 to 3 hr/ day (OR: 1.48, 95% CI: 1.24, 1.76) and ≥ 4 hr/day (OR: 1.52, 95% CI: 1.22, 1.91) daily TV groups compared with

none. Reading and nonschool computer usage was not associated with being overweight.
CONCLUSIONS:
TV was associated with overweight classification; however, nonschool computer usage and read- ing were not. Several individual, family, and community correlates were associated with high vol- umes of daily TV viewing. PMID: 21918232

Screen-based Entertainment Time, All-cause Mortality, and Cardiovascular Events: Popu- lation-based Study With Ongoing Mortality and Hospital Events Follow-up

Emmanuel Stamatakis, PhD, MSc, BSc; Mark Hamer, PhD, MSc, BSc; David W. Dunstan, PhD, BAppSc; Journal of the American College of Cardiology. 2011;57(3):292-299.
Authors and Disclosures

6

Posted: 01/20/2011; J Am Coll Cardiol. 2011;57(3):292-299. © 2011 Elsevier Science, Inc.

Abstract
Objectives The aim of this study was to examine the independent relationships of television view- ing or other screen-based entertainment ("screen time") with all-cause mortality and clinically confirmed cardiovascular disease (CVD) events. A secondary objective was to examine the extent to which metabolic (body mass index, high-density lipoprotein and total cholesterol) and inflam- matory (C-reactive protein) markers mediate the relationship between screen time and CVD events.

Background Although some evidence suggests that prolonged sitting is linked to CVD risk factor development regardless of physical activity participation, studies with hard outcomes are scarce. Methods A population sample of 4,512 (1,945 men) Scottish Health Survey 2003 respondents (≥35 years) were followed up to 2007 for all-cause

mortality and CVD events (fatal and nonfatal combined). Main exposures were interviewer-assessed screen time (<2 h/day; 2 to <4 h/ day; and ≥4 h/day) and moderate to vigorous intensity physical activity.

Results Two hundred fifteen CVD events and 325 any-cause deaths occurred during 19,364 fol- low-up person-years. The covariable (age, sex, ethnicity, obesity, smoking, social class, long- standing illness, marital status, diabetes, hypertension)-adjusted hazard ratio (HR) for all- cause mortality was 1.52 (95% confidence interval [CI]: 1.06 to 2.16) and for CVD events was 2.30 (95% CI: 1.33 to 3.96) for participants engaging in ≥4 h/day of screen time relative to <2 h/day. Adjusting for physical activity attenuated these associations only slightly (all-cause mortality: HR: 1.48, 95% CI: 1.04 to 2.13; CVD events: HR: 2.25, 95% CI: 1.30 to 3.89). Exclusion of par- ticipants with CVD events in the first 2 years of follow-up and previous cancer registrations did not change these results appreciably. Approximately 25% of the association between screen time and CVD events was explained collectively by C-reactive protein, body mass index, and high- density lipoprotein cholesterol.

Conclusions Recreational sitting, as reflected by television/screen viewing time, is related to raised mortality and CVD risk regardless of physical activity participation. Inflammatory and metabolic risk factors partly explain this relationship.

Introduction
There is indisputable evidence on the links between physical activity and risk for premature death.[1] Some emerging published reports consistently suggest that excessive sedentary behavior (as characterized by those activities involving sitting) might be linked to increased risk for obe- sity,[2,3] dyslipidemia,[4] plasma glucose levels,[5] and the metabolic syndrome[6] indepen- dently of moderate-to-vigorous physical activity participation. Television viewing and screen- based entertainment (screen time) in general seems to be the most important indicator of nonoccu- pational sitting behavior.[7] Recent time-use

surveys[8–10] indicate that, aside from sleeping, watching TV is the behavior that occupies the most time in the domestic setting.

If sitting or total sedentary time is established to be independently associated with cardiovascular disease (CVD), clinical and public health recommendations should explicitly address sitting in addition to physical activity; currently they do not.[11] Because only a minority of adults in west-

7

ern populations participate regularly in sport and exercise activities, [12,13] and those who do not take part in sports are more likely to develop CVD or die prematurely,[14] it might be possible to reduce the risk of nonparticipants by restricting sitting time and increasing nonexercise activity (e.g., standing and ambulating) throughout the day. [15] There is no conclusive evidence obtained from comparing the feasibility or long-term effectiveness of interventions designed to increase formal exercise versus decreasing sitting behavior during the day. However, the latter approach might be more promising in terms of long-term adherence, because it will involve more subtle lif- estyle changes and fewer of the commonly cited barriers[16] for joining a sporting or lifestyle exercise program.

The primary aim of this study was to examine the relationships of leisure-time sitting behavior (indexed from screen time) with all-cause mortality and CVD events while taking multiple mea- sures to address reverse causality. Because it is also important to understand the mechanisms through which sedentary behavior might influence cardiovascular risk, a secondary aim was to determine the extent to which several biomarkers explain these relationships. http:// www.medscape.com/viewarticle/735696

Riding in a Car and TV Viewing

Med Sci Sports Exerc. 2010 May;42(5):879-85.
Sedentary behaviors increase risk of cardiovascular disease mortality in men. Warren TY, Barry V, Hooker SP, Sui X, Church TS, Blair SN.

15

Source
Department of Exercise Science, Arnold School of Public Health, University of South Carolina, Columbia, SC 29208, USA. warrenty@mailbox.sc.edu
Abstract
PURPOSE:
The purpose of this study was to examine the relationship between two sedentary behaviors (riding in a car and watching TV) and cardiovascular disease (CVD) mortality in men in the Aer- obics Center Longitudinal Study.
METHODS:
Participants were 7744 men (20-89 yr) initially free of CVD who returned a mail-back survey dur- ing 1982. Time spent watching TV and time spent riding in a car were reported. Mortality data were ascertained through the National Death Index until December 31, 2003. Cox regression anal- ysis quantified the association between sedentary behaviors (hours per week watching TV, hours per week riding in a car, and total hours per week in these two behaviors) and CVD mortality rates.
RESULTS:
Three hundred and seventy-seven CVD deaths occurred during 21 yr of follow-up. After age adjustment, time riding in a car and combined time spent in these two sedentary behaviors were positively (P(trend) < 0.001) associated with CVD death. Men who reported >10 h x wk(-1) riding in a car or >23 h x wk(-1) of combined sedentary behavior had 82% and 64% greater risk of dying from CVD than those who reported <4 or <11 h x wk(-1), respectively. The pattern of the association did not materially change after multivariate adjustment. Regardless of the amount of sedentary activity reported by these men, being older, having

normal weight, being normotensive, and being physically active were associated with a reduced risk of CVD death.
CONCLUSION:
In men, riding in a car and combined time spent in these two sedentary behaviors were significant CVD mortality predictors. In addition, high levels of physical activity were related to notably lower rates of CVD death even in the presence of high levels of sedentary behavior. Health pro- motion efforts targeting physically inactive men should emphasize both reducing sedentary activ- ity and increasing regular physical activity for optimal cardiovascular health.

PMID: 19996993 (http://www.ncbi.nlm.nih.gov/pubmed/19996993)

Moderate to vigorous physical activity and sedentary time and cardiometabolic risk factors in children and adolescents.

JAMA. 2012 Feb 15;307(7):704-12. doi: 10.1001/jama.2012.156. Ekelund U, Luan J, Sherar LB, Esliger DW, Griew P, Cooper A; International Children's Accelerometry Database (ICAD) Collaborators. Collaborators (16)

Source
MRC Epidemiology Unit, Institute of Metabolic Science, Addenbrookes Hospital, PO Box 285, Cambridge, CB2 0QQ, Cambridge, United Kingdom. ulf.ekelund@mrc-epid.cam.ac.uk
Erratum in
JAMA. 2012 May 9;307(18):1915. Sardinha L [corrected to Sardinha, L B]; Anderssen, S A [cor- rected to Anderson, L B].
Abstract
CONTEXT:
Sparse data exist on the combined associations between physical activity and sedentary time with cardiometabolic risk factors in healthy children. OBJECTIVE:
To examine the independent and combined associations between objectively measured time in moderate- to vigorous-intensity physical activity (MVPA) and sedentary time with cardiometa- bolic risk factors.

[page48image13584]

DESIGN, SETTING, AND PARTICIPANTS:
Pooled data from 14 studies between 1998 and 2009 comprising 20 871 children (aged 4-18 years) from the International Children's Accelerometry Database. Time spent in MVPA and sed- entary time were measured using accelerometry after reanalyzing raw data. The independent asso- ciations between time in MVPA and sedentary time, with outcomes, were examined using meta- analysis. Participants were stratified by tertiles of MVPA and sedentary time.
MAIN OUTCOME MEASURES:
Waist circumference, systolic blood pressure, fasting triglycerides, high- density lipoprotein cho- lesterol, and insulin.
RESULTS:
Times (mean [SD] min/d) accumulated by children in MVPA and being sedentary were 30 (21) and 354 (96), respectively. Time in MVPA was significantly associated with all cardiometabolic outcomes independent of sex, age, monitor wear time, time spent sedentary, and waist circumference (when not the outcome). Sedentary time was not associated with any outcome independent of time in MVPA. In the combined analyses, higher levels of MVPA were associated with better cardiometabolic risk factors across tertiles of sedentary time. The differences in outcomes between higher and lower MVPA were greater with lower sedentary time. Mean differences in waist circumference between the bottom and top tertiles of MVPA were 5.6 cm (95% CI, 4.8-6.4 cm) for high sedentary time and 3.6 cm (95% CI, 2.8-4.3 cm) for low sedentary time. Mean differ- ences in systolic blood pressure for high and low sedentary time were 0.7 mm Hg (95% CI, -0.07 to 1.6) and 2.5 mm Hg (95% CI, 1.7-3.3), and for high-density lipoprotein cholesterol, differences were -2.6 mg/dL (95% CI, -1.4 to -3.9) and -4.5 mg/dL (95% CI, -3.3 to -5.6), respectively. Geo-metric mean differences for insulin and triglycerides showed similar variation. Those in the top tertile of MVPA accumulated more than 35 minutes per day in this intensity level compared with fewer than 18 minutes per day for those in the bottom tertile. In prospective analyses (N = 6413 at 2.1 years' follow-up), MVPA and sedentary time were not associated with waist

circumference at follow-up, but a higher waist circumference at baseline was associated with higher amounts of sedentary time at follow-up.

CONCLUSION:
Higher MVPA time by children and adolescents was associated with better cardiometabolic risk factors regardless of the amount of sedentary time.
Comment in
Time spent sedentary and active and cardiometabolic risk factors in children. [JAMA. 2012] Youth physical activity and sedentary time and associations with cardiometabolic health. [Evid Based Nurs. 2012]PMID: 22337681

Reducing Children's Television Viewing to Prevent Obesity

A Randomized Controlled Trial
1.Thomas N. Robinson, MD, MPH
[+] Author Affiliations
1.Author Affiliation: Departments of Pediatrics and Medicine, Stanford Center for Research in Disease Prevention, Stanford University School of Medicine, Palo Alto, Calif.

ABSTRACT
Context Some observational studies have found an association between television viewing and child and adolescent adiposity.
Objective To assess the effects of reducing television, videotape, and video game use on changes in adiposity, physical activity, and dietary intake.
Design Randomized controlled school-based trial conducted from September 1996 to April 1997. Setting Two sociodemographically and scholastically matched public elementary schools in San Jose, Calif.

Participants Of 198 third- and fourth-grade students, who were given parental consent to partici- pate, 192 students (mean age, 8.9 years) completed the study.

Intervention Children in 1 elementary school received an 18-lesson, 6- month classroom curricu- lum to reduce television, videotape, and video game use.

Main Outcome Measures Changes in measures of height, weight, triceps skinfold thickness, waist and hip circumferences, and cardiorespiratory fitness; self-reported media use, physical activity, and dietary behaviors; and parental report of child and family behaviors. The primary outcome measure was body mass index, calculated as weight in kilograms divided by the square of height in meters.

Results Compared with controls, children in the intervention group had statistically significant relative decreases in body mass index (intervention vs control change: 18.38 to 18.67 kg/m2 vs 18.10 to 18.81 kg/m2, respectively; adjusted difference ?0.45 kg/m2 [95% confidence interval {CI}, ?0.73 to ?0.17]; P=.002), triceps skinfold thickness (intervention vs control change: 14.55 to 15.47 mm vs 13.97 to 16.46 mm, respectively; adjusted difference, ?1.47 mm [95% CI, ?2.41 to ? 0.54]; P=.002), waist circumference (intervention vs control change: 60.48 to 63.57 cm vs 59.51 to 64.73 cm, respectively; adjusted difference, ?2.30 cm [95% CI, ?3.27 to ?1.33]; P<.001), and waist-to-hip ratio (intervention vs control change: 0.83 to 0.83 vs 0.82 to 0.84, respectively; adjusted difference, ?0.02 [95% CI, ?0.03 to ?0.01]; P<. 001). Relative to controls, intervention group changes were accompanied by statistically significant decreases in children's reported tele- vision viewing and meals eaten in front of the television. There were no statistically significant differences between groups for changes in high-fat food intake, moderate-to-vigorous physical activity, and cardiorespiratory fitness.

Conclusions Reducing television, videotape, and video game use may be a promising, population-based approach to prevent childhood obesity. http://jama.ama-assn.org/content/282/16/1561
“This is the first experimental study to demonstrate a direct association between television, video- tape, and video game use and increased

[page51image15992]

adiposity. Because the intervention targeted reduction of media use alone, without substituting alternative behaviors, a causal inference might be made.23 In one previous obesity treatment study, obese children who were reinforced (ie, rewarded) for decreasing sedentary activity (including television viewing and computer games, as well as imag- inative play, talking on the telephone, playing board games, etc) along with following an energy- restricted diet lost significantly more weight than obese children reinforced for increasing physial activity or those reinforced for both.44 Although that study did not directly test the role of tele- vision, videotape, and video game use, the similar findings support our results.”

FULL TEXT http://jama.ama-assn.org/content/282/16/1561.full Television Viewing as a Cause of Increasing Obesity Among

Children in the United States, 1986-1990

Steven L. Gortmaker, PhD; Aviva Must, PhD; Arthur M. Sobol, AM; Karen Peterson, RD, ScD; Graham A. Colditz, MD, DrPH; William H. Dietz, MD, PhD
Arch Pediatr Adolesc Med. 1996;150(4):356-362.

Background and Methods

The prevalence of obesity among children and adolescents has increased, and television viewing has been suggested as a cause. We examined the relation between hours of television viewed and the prevalence of overweight in 1990, and the incidence and remission of overweight from 1986 to 1990 in a nationally representative cohort of 746 youths aged 10 to 15 years in 1990 whose mothers were 25 to 32 years old. Overweight was defined as a body mass index higher than the 85th percentile for age and gender.

Results
We observed a strong dose-response relationship between the prevalence of overweight in 1990 and hours of television viewed. The odds of being overweight were 4.6 (95% confidence inter- val, 2.2 to 9.6)

[page52image15704]

times greater for youth watching more than 5 hours of television per day com- pared with those watching for 0 to 2 hours. When adjustments were made for previous overweight (in 1986), baseline maternal overweight, socioeconomic status, household structure, ethnicity, and maternal and child aptitude test scores, results were similar (odds ratio, 5.3; 95% confidence interval, 2.3 to 12.1). We also found significant relations between television viewing and increased incidence and decreased remission of overweight during this 4-year period, adjusted for baseline covariates. The adjusted odds of incidence were 8.3 (95% confidence interval, 2.6 to 26.5) times greater for youth watching more than 5 hours of television per day com- pared with those watching for 0 to 2 hours. Estimates of attributable risk indicate that more 60% of overweight incidence in this population can be linked to excess television viewing time.

Conclusion
Television viewing affects overweight among youth, and reductions in viewing time could help prevent this increasingly common chronic health condition.
(Arch Pediatr Adolesc Med. 1996;150:356-362

Volume, patterns, and types of sedentary behavior and cardio- metabolic health in children and adolescents: a cross-sectional study

Valerie Carson1 and Ian Janssen1,2*
•Corresponding author: Ian Janssen ian.janssen@queensu.ca
Author Affiliations
1School of Kinesiology and Health Studies, Queen's University, Kingston, ON, Canada 2Department of Community Health and Epidemiology, Queen's University, Kingston, ON, Can- ada
For all author emails, please log on. BMC Public Health 2011, 11:274 doi:10.1186/1471-2458- 11-274

The electronic version of this article is the complete one and can be found online at: http:// www.biomedcentral.com/1471-2458/11/274 Published: 4 May 2011

[page53image14872] [page53image15032]

This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/ licenses/by/2.0), which permits unrestricted use, distribu- tion, and reproduction in any medium, provided the original work is properly cited.
Abstract

Background
Cardio-metabolic risk factors are becoming more prevalent in children and adolescents. A lack of moderate-to-vigorous intensity physical activity (MVPA) is an established determinant of cardio- metabolic risk factors in children and adolescents. Less is known about the relationship between sedentary behavior and cardio-metabolic health. Therefore, the objective was to examine the inde- pendent associations between volume, patterns, and types of sedentary behavior with cardio-met- abolic risk factors among children and adolescents.
Methods
The results are based on 2527 children and adolescents (6-19 years old) from the 2003/04 and 2005/06 National Health and Nutrition Examination Surveys (NHANES). A cardio-metabolic risk score (CRS) was calculated based on age- and sex-adjusted waist circumference, systolic blood pressure, non-high-density lipoprotein cholesterol, and C- reactive protein values. Volume and pat- terns of sedentary behavior and moderate-to-vigorous physical activity (MVPA) were measured objectively using accelerometers. Types of sedentary behavior were measured by questionnaire. A series of logistic regression models were used to examine associations.
Results
Volume and patterns of sedentary behavior were not predictors of high CRS after adjusting for MVPA and other confounders (P > 0.1). For types of sedentary behavior, high TV use, but not high computer use, was a predictor of high CRS after adjustment for MVPA and other confounders. Children and adolescents who watched ≥4 hours per day of TV were 2.53 (95% confidence interval: 1.45-4.42) times more likely to

[page54image15000] [page54image15160]

have high CRS than those who watched <1 hour per day. MVPA predicted high CRS after adjusting for all sedentary behavior measures and other confounders. After adjustment for waist circumference,
MVPA also predicted high non-obesity CRS; however, the same relationship was not seen with TV use.
Conclusion
No association was observed between overall volume and patterns of sedentary behavior with car- dio-metabolic risk factors in this large sample of children and adolescents. Conversely, high TV use and low MVPA were independently associated with cardio-metabolic risk factors. However, the association between high TV use and clustered cardio- metabolic risk factors appears to be mediated or confounded by obesity. Thus, TV and MVPA appear to be two separate behaviors that need to be targeted with different interventions and policies.
Systematic review of sedentary behaviour and health indicators in school-aged children and youth

Mark S Tremblay1*, Allana G LeBlanc1, Michelle E Kho2, Travis J Saunders1, Richard Larouche1, Rachel C Colley1, Gary Goldfield1 and Sarah C Gorber3
International Journal of Behavioral Nutrition and Physical Activity 2011, 8:98 doi:10.1186/1479- 5868-8-98; Published: 21 September 2011

Researchers at the Healthy Active Living and Obesity Research Group in the Children’s Hospital of Eastern Ontario Research Institute have published the world’s first systematic review of seden- tary behaviour and health in school-aged children, which were used to inform Canada’s Sedentary Behaviour Guidelines.

Accumulating evidence suggests that, independent of physical activity levels, sedentary behav- iours are associated with increased risk of cardio-metabolic disease, all-cause mortality, and a variety of physiological and psychological problems. Therefore, the purpose of this systematic review is to determine the relationship between sedentary behaviour and health indicators in school-aged children and youth aged

5-17 years. Online databases (MEDLINE, EMBASE and PsycINFO), personal libraries, and government documents were searched for relevant studies examining time spent engaging in sedentary behaviours and six specific health indicators (body composition, fitness, metabolic syndrome and cardiovascular disease, self-esteem, pro-social behaviour and academic achievement). 232 studies including 983,840 participants met inclusion criteria and were included in the review. Television (TV) watching was the most common measure of sedentary behaviour and body composition was the most common outcome measure. Qualitative analysis of all studies revealed a dose-response relation between increased sedentary behaviour and unfavourable health outcomes. Watching TV for more than 2 hours per day was associated with unfavourable body composition, decreased fitness, lowered scores for self-esteem and pro-social behaviour and decreased academic achievement. Meta analysis was completed for randomized controlled studies that aimed to reduce sedentary time and reported change in body mass index (BMI) as their primary outcome. In this regard, a meta- analysis revealed an overall significant effect of -0.81 (95% CI of -1.44 to -0.17, p=0.01) indicat- ing an overall decrease in mean BMI associated with the interventions. There is a large body of evidence from all study designs which suggests that decreasing any type of sedentary time is associated with lower health risk in youth aged 5-17 years. In particular, the evidence suggests that daily TV viewing in excess of 2 hours is associated with reduced physical and psychosocial health, and that lowering sedentary time leads to reductions in BMI. http:// www.ijbnpa.org/content/8/1/98/abstract

Are computer and cell phone use associated with body mass index and overweight? A population study among twin adolescents

BMC Public Health. 2007; 7: 24.
Published online 2007 February 26. doi: 10.1186/1471-2458-7-24 PMCID: PMC1820777
Copyright © 2007 Lajunen et al; licensee BioMed Central Ltd.

[page56image16008] [page56image16168]

Hanna-Reetta Lajunen,1 Anna Keski-Rahkonen,#1,2,3 Lea Pulkkinen,#4 Richard J Rose,#1,5 Aila Rissanen,#2 and Jaakko Kaprio#1,6

Abstract Background

Overweight in children and adolescents has reached dimensions of a global epidemic during recent years. Simultaneously, information and communication technology use has rapidly increased.
Methods

A population-based sample of Finnish twins born in 1983–1987 (N = 4098) was assessed by self- report questionnaires at 17 y during 2000– 2005. The association of overweight (defined by Cole's BMI-for-age cut- offs) with computer and cell phone use and ownership was analyzed by logistic regression and their association with BMI by linear regression models. The effect of twinship was taken into account by correcting for clustered sampling of families. All models were adjusted for gender, physical exercise, and parents' education and occupational class.

Results

The proportion of adolescents who did not have a computer at home decreased from 18% to 8% from 2000 to 2005. Compared to them, having a home computer (without an Internet connection) was associated with a higher risk of overweight (odds ratio 2.3, 95% CI 1.4 to 3.8) and BMI (beta coefficient 0.57, 95% CI 0.15 to 0.98). However, having a computer with an Internet connection was not associated with weight status. Belonging to the highest quintile (OR 1.8 95% CI 1.2 to 2.8) and second-highest quintile (OR 1.6 95% CI 1.1 to 2.4) of weekly computer use was posi- tively associated with overweight. The proportion of adolescents without a personal cell phone decreased from 12% to 1% across 2000 to 2005. There was a positive linear trend of increasing monthly phone bill with BMI (beta 0.18, 95% CI 0.06 to 0.30), but the association of a cell phone bill with overweight was very weak.

Conclusion
Time spent using a home computer was associated with an increased risk of overweight. Cell phone use correlated weakly with BMI. Increasing use of information and communication tech- nology may be related to the obesity epidemic among adolescents. http://www.ncbi.nlm.nih.gov/ pmc/articles/PMC1820777/

The Impact of Stand-Biased Desks in Classrooms on Calorie Expenditure in Children.

Mark E. Benden, Jamilia J. Blake, Monica L. Wendel, and John C. Huber Jr American Journal of Public Health: August 2011, Vol. 101, No. 8, pp. 1433-1436. doi: 10.2105/AJPH.2010.300072

Childhood obesity is a public health concern with significant health and economic impacts. We conducted a prospective experimental study in 4 classrooms in central Texas to determine the effect of desks that encourage standing rather than sitting on caloric expenditure in children. Students were monitored with calorie expenditure–measuring arm-bands worn for 10 days in the fall and spring. The treatment group experienced significant increases in calorie expenditure over the control group, a finding that has implications for policy and practice. http:// ajph.aphapublications.org/doi/abs/10.2105/AJPH.2010.300072

Cholesterol

"Television viewing time was associated with lower high-density lipoprotein cholesterol (HDL-C) levels"

J Am Geriatr Soc. 2011 May;59(5):788-96. doi: 10.1111/j. 1532-5415.2011.03390.x. Associations between television viewing time and overall sitting time with the metabolic syndrome in older men and women: the Australian Diabetes, Obesity and Lifestyle study.
Gardiner PA, Healy GN, Eakin EG, Clark BK, Dunstan DW, Shaw JE, Zimmet PZ, Owen N. Source
Cancer Prevention Research Centre, School of Population Health,

[page58image14104] [page58image14264] [page58image14424] [page58image14584]

University of Queensland, Brisbane, Queensland, Australia.

p.gardiner@uq.edu.au

Abstract
OBJECTIVES:
To examine associations between self-reported television (TV) viewing time and overall sitting time with the metabolic syndrome and its components.
DESIGN:
Cross-sectional.
SETTING:
Population-based sample of older men and women living in Australia. PARTICIPANTS:
One thousand nine hundred fifty-eight participants from the Australian Diabetes, Obesity and Lif- estyle (AusDiab) study (aged ≥ 60, mean age 69, 54% women).
MEASUREMENTS:
Self-reported television viewing time and overall sitting time were collected using an interviewer- administered questionnaire. The metabolic syndrome was defined according to the revised Inter- national Diabetes Federation criteria.
RESULTS:
Compared with those in the lowest quartile, the odds ratios (ORs) of the metabolic syndrome in the highest quartile of television viewing time were 1.42 (95% confidence interval (CI)=0.93- 2.15) for men and 1.42 (95% CI=1.01-2.01) for women and in the highest quartile of overall sit- ting time were 1.57 (95% CI=1.02-2.41) for men and 1.56 (95% CI=1.09-2.24) for women. Tele- vision viewing time was associated with lower high-density lipoprotein cholesterol (HDL-C) levels and glucose intolerance in women. Overall sitting time was detrimentally associated with greater risk of high triglyceride levels in men and women, abdominal obesity in women, and low HDL-C levels in men. All models were adjusted for age, education, physical activity, self-rated health, employment, diet, smoking, and alcohol intake and for hormone replacement therapy and estrogen use in women.

[page59image13808]

CONCLUSION:
For older adults, high levels of sedentary behavior were associated with greater prevalence of the metabolic syndrome; reducing prolonged overall sitting time may be a feasible way to improve metabolic health. © 2011, Copyright the Authors. Journal compilation © 2011, The American Geriatrics Society. PMID: 21568949

Commercial stepping

Can sedentary behavior be made more active? A randomized pilot study of TV commercial stepping versus walking.

Steeves JA, Bassett DR, Fitzhugh EC, Raynor HA, Thompson DL. Int J Behav Nutr Phys Act. 2012 Aug 6;9:95. doi: 10.1186/1479-5868-9-95.
Source

Cancer Prevention Fellowship Program, National Cancer Institute, 6120 Executive Boulevard, Bethesda, MD, 20892, USA. jeremy.steeves@nih.gov
Abstract

BACKGROUND:
There is a growing problem of physical inactivity in America, and approximately a quarter of the population report being completely sedentary during their leisure time. In the U.S., TV viewing is the most common leisure-time activity. Stepping in place during TV commercials (TV Commer- cial Stepping) could increase physical activity. The purpose of this study was to examine the fea- sibility of incorporating physical activity (PA) into a traditionally sedentary activity, by comparing TV Commercial Stepping during 90 min/d of TV programming to traditional exercise (Walking).
METHODS:
A randomized controlled pilot study of the impact of 6 months of TV Commercial Stepping versus Walking 30 min/day in adults was conducted. 58 sedentary, overweight (body mass index 33.5?±?4.8 kg/

[page60image13552]

m2) adults (age 52.0?±?8.6 y) were randomly assigned to one of two 6- mo behavioral PA programs: 1) TV Commercial Stepping; or 2) Walking 30 min/day. To help facili- tate behavior changes participants received 6 monthly phone calls, attended monthly meetings for the first 3 months, and received monthly newsletters for the last 3 months. Using intent-to- treat analysis, changes in daily steps, TV viewing, diet, body weight, waist and hip circumference, and percent fat were compared at baseline, 3, and 6 mo. Data were collected in 2010-2011, and ana- lyzed in 2011. RESULTS:

Of the 58 subjects, 47 (81%) were retained for follow-up at the completion of the 6-mo program. From baseline to 6-mo, both groups significantly increased their daily steps [4611?±?1553 steps/d vs. 7605? ±?2471 steps/d (TV Commercial Stepping); 4909?±?1335 steps/d vs. 7865?±?1939 steps/d (Walking); P?<?0.05] with no significant difference between groups. TV viewing and dietary intake decreased significantly in both groups. Body weight did not change, but both groups had significant decreases in percent body fat (3-mo to 6-mo), and waist and hip cir- cumference (baseline to 6-mo) over time. CONCLUSIONS:
Participants in both the TV Commercial Stepping and Walking groups had favorable changes in daily steps, TV viewing, diet, and anthropometrics. PA can be performed while viewing TV com- mercials and this may be a feasible alternative to traditional approaches for increasing daily steps in overweight and obese adults.
TRIAL REGISTRATION:
This study is registered at ClinicalTrials.gov, NCT01342471.

PMID: 22866941

Energy cost of stepping in place while watching television commercials.

Steeves JA, Thompson DL, Bassett DR Jr.
Med Sci Sports Exerc. 2012 Feb;44(2):330-5. doi: 10.1249/MSS. 0b013e31822d797e.

Source
Department of Kinesiology, Recreation, and Sport Studies, University of Tennessee, Knoxville, TN 37996, USA. jsteeves@utk.edu
Abstract
INTRODUCTION:
Modifying sedentary television (TV) watching behaviors by stepping in place during commercials (TV commercial stepping) could increase physical activity and energy expenditure.
PURPOSE:
The study's purpose was to determine the energy cost of TV commercial stepping and to quantify the amount of activity (number of steps and minutes) performed during 1 h of TV commercial stepping. METHODS:
In part 1, 23 adults (27.8 ± 7.0 yr) had their energy expenditure measured at rest, sitting, standing, stepping in place, and walking at 3.0 mph on the treadmill. The second part of this study involved 1 h of sedentary TV viewing and 1 h of TV commercial stepping. Actual steps were counted with a hand tally counter.
RESULTS:
There were no differences (P = 0.76) between the caloric requirements of reclining rest (79 ± 16 kcal·h(-1)) and sedentary TV viewing (81 ± 19 kcal·h(-1)). However, stepping in place (258 ± 76 kcal·h(-1)), walking at 3.0 mph on the treadmill (304 ± 71 kcal·h(-1)), and 1 h of TV commercial stepping (148 ± 40 kcal·h(-1)) had a higher caloric requirement than either reclining rest or seden- tary TV viewing (P < 0.001). One hour of TV commercial stepping resulted in an average of 25.2 ± 2.6 min of physical activity and 2111 ± 253 steps. CONCLUSIONS:
Stepping in place during commercials can increase the energy cost and amount of activity performed during TV viewing.
PMID: 21760553

Depression

[page62image14368]

Associations of objectively-assessed physical activity and sedentary time with depression:

Prev Med. 2011 Oct;53(4-5):284-8. Epub 2011 Jul 23. NHANES (2005-2006).

Vallance JK, Winkler EA, Gardiner PA, Healy GN, Lynch BM, Owen N. Source
Athabasca University, Athabasca, AB, Canada. jeffv@athabascau.ca Abstract

BACKGROUND:
Studies provide conflicting evidence for the protective effects of moderate-to-vigorous-intensity physical activity on depression. Recent evidence suggests that sedentary behaviors may also be associated with depression.
PURPOSE:
To examine the associations of accelerometer-derived moderate-to- vigorous-intensity physical activity and sedentary time with depression among a population-based sample.
METHODS:
Cross-sectional study using 2,862 adults from the 2005-2006 US National Health and Nutrition Examination Survey. ActiGraph accelerometers were used to derive both moderate-to-vigorous- intensity physical activity and sedentary time.
RESULTS:
Depression occurred in 6.8% of the sample. For moderate-to-vigorous- intensity physical activity, compared with those in quartile 1 (least active), significantly lower odds of depression were observed for those participants in quartiles 2 (OR=0.55, 95% CI, 0.34 to 0.89), 3 (OR=0.49, 95% CI, 0.26 to 0.93), and 4 (most active) (OR=0.37, 95% CI, 0.20 to 0.70) (p for trend p<0.01). In overweight/obese participants only, those in quartile 4 (most sedentary) had significantly higher odds for depression than those in quartile 1 (least sedentary) [quartile 3 vs 1 (OR=1.94, 95% CI, 1.01 to 3.68) and 4 vs 1 (OR=3.09, 95% CI, 1.25 to

[page63image13312]

7.68)].
CONCLUSION:
The current study identified lower odds of depression were associated with increasing moderate- to-vigorous-intensity physical activity and decreasing sedentary time, at least within overweight/ obese adults. http://www.ncbi.nlm.nih.gov/pubmed/21820466

Diabetes / Glucose / Insulin

Television Viewing Increases Risk of Type 2 Diabetes, Cardiovascular Disease, and Mortality

Grontved A, Hu, FB: Television viewing and risk of type 2 diabetes, cardiovascular disease, and all-cause mortality. JAMA 305:2448–2455, 2011
SUMMARY

Design. A meta-analysis of prospective observational studies.

Subjects. The meta-analysis included eight prospective observational studies. (Four studies exam- ined type 2 diabetes; four studies examined fatal or nonfatal cardiovascular disease [CVD]; and three studies examined all-cause mortality.) The four studies addressing type 2 diabetes included 175,938 participants; the four studies examining fatal or nonfatal CVD had a total of 34,253 participants; and the three studies that examined all-cause mortality included 26,509 participants. Mean follow-up duration was 8.5 years for studies examining type 2 diabetes, 10 years for those examining fatal or nonfatal CVD, and 7 years for those addressing all-cause mortality. Each of the study populations was healthy at baseline

Methods

The goal of the meta-analysis was to determine the association between TV viewing and the risk of type 2 diabetes, fatal or nonfatal CVD, and all-cause mortality. Random effects models were used to pool relative risk (RR) estimates, and heterogeneity among studies was examined by

[page64image13672]

I2 statistics. Sensitivity analyses evaluated whether meta-analysis results could have been affected by a single study.

Results.
The pooled RR of developing type 2 diabetes per every 2 hours of TV watching per day was 1.20 (95% CI 1.14–1.27). The risk of fatal or nonfatal cardiovascular events was 1.15 (95% CI 1.05– 1.23), and risk for all-cause mortality was 1.13 (95% CI 1.07–1.18). Risk of all-cause mortality appeared to increase at a threshold of > 3 hours of television watching per day, but both type 2 diabetes and CVD had linear increases in risk with each additional 2 hours per day of TV watch- ing. Data were not available to fully assess the degree to which dietary intake and physical inac- tivity explain the negative effects of TV viewing on outcomes.

Conclusion. TV viewing was associated with increased risk of type 2 diabetes, cardiovascular events, and all-cause mortality in a dose- dependent manner.

Physical activity and television viewing in relation to risk of undiagnosed abnormal glucose metabolism in adults.

Authors: Dunstan DW, Salmon J, Owen N, et al.
Institution: International Diabetes Institute, Melbourne, Australia 3162. ddunstan@idi.org.au Source: Diabetes Care 2004 Nov; 27(11) :2603-9. Abstract
OBJECTIVE
The goal of this study was to assess the associations of physical activity time and television (TV) time with risk of "undiagnosed" abnormal glucose metabolism in Australian adults.
RESEARCH DESIGN AND METHODS
This population-based cross-sectional study using a stratified cluster design involving 42 ran- domly selected Census Collector Districts across Australia included 8,299 adults aged 25 years or older who were free from new type 2 diabetes and self-reported ischemic disease and did

[page65image15240]

not take lipid-lowering or antihypertensive drugs. Abnormal glucose metabolism (impaired fasting glyce- mia [IFG], impaired glucose tolerance [IGT], or new type 2 diabetes) was based on an oral glu- cose tolerance test. Self-reported physical activity time and TV time (previous week) were assessed using interviewer-administered questionnaires. RESULTS

After adjustment for known confounders and TV time, the odds ratio (OR) of having abnormal glucose metabolism was 0.62 (95% CI 0.41-0.96) in men and 0.71 (0.50-1.00) in women for those engaged in physical activity >or=2.5 h/week compared with those who were sedentary (0 h/ week). The ORs of having abnormal glucose metabolism were 1.16 (0.79-1.70) in men and 1.49 (1.12-1.99) in women who watched TV >14 h/week compared with those who watched <or=7.0 h/ week. Higher TV viewing (>14 h/week) was also associated with an increased risk of new type 2 diabetes in men and women and IGT in women compared with those watching <14 h/week. Total physical activity of >or=2.5 h/week was associated with a reduced risk of IFG, IGT, and new type 2 diabetes in both sexes; however, only the association with IGT in women was statisti- cally significant. CONCLUSIONS

These findings suggest a protective effect of physical activity and a deleterious effect of TV time on the risk of abnormal glucose metabolism in adults. Population strategies to reduce risk of

abnormal glucose metabolism should focus on reducing sedentary behaviors such as TV time, as well as increasing physical activity. http:// www.hopkinsguides.com/hopkins/ub/citation/15504993/

Minimal intensity physical activity (standing and walking) of longer duration improves insulin action and plasma lipids more than shorter periods of moderate to vigorous exercise (cycling) in sedentary subjects when energy expenditure is comparable.

Duvivier BM1, Schaper NC, Bremers MA, van Crombrugge G, Menheere PP, Kars M, Savelberg HH.

[page66image16544] [page66image16704] [page66image16864] [page66image17024] [page66image17184] [page66image17344] [page66image17504] [page66image17664] [page66image17824]

Abstract

BACKGROUND:

Epidemiological studies suggest that excessive sitting time is associated with increased health risk, independent of the performance of exercise. We hypothesized that a daily bout of exercise cannot compensate the negative effects of inactivity during the rest of the day on insulin sensitivity and plasma lipids.

METHODOLOGY/PRINCIPAL FINDINGS:

Eighteen healthy subjects, age 21±2 year, BMI 22.6±2.6 kgm(-2) followed randomly three physical activity regimes for four days. Participants were instructed to sit 14 hr/day (sitting regime); to sit 13 hr/day and to substitute 1 hr of sitting with vigorous exercise 1 hr (exercise regime); to substitute 6 hrs sitting with 4 hr walking and 2 hr standing (minimal intensity physical activity (PA) regime). The sitting and exercise regime had comparable numbers of sitting hours; the exercise and minimal intensity PA regime had the same daily energy expenditure. PA was assessed continuously by an activity monitor (ActivPAL) and a diary. Measurements of insulin sensitivity (oral glucose tolerance test, OGTT) and plasma lipids were performed in the fasting state, the morning after the 4 days of each regime. In the sitting regime, daily energy expenditure was about 500 kcal lower than in both other regimes. Area under the curve for insulin during OGTT was significantly lower after the minimal intensity PA regime compared to both sitting and exercise regimes 6727.3±4329.4 vs 7752.0±3014.4 and 8320.4±5383.7 mU•min/ml, respectively. Triglycerides, non-HDL cholesterol and apolipoprotein B plasma levels improved significantly in the minimal intensity PA regime compared to sitting and showed non-significant trends for improvement compared to exercise.

CONCLUSIONS:

One hour of daily physical exercise cannot compensate the negative effects of inactivity on insulin level and plasma lipids if the rest of the day is spent sitting. Reducing inactivity by increasing the time spent walking/standing is more effective than one hour of physical exercise, when energy expenditure is kept constant.

PMID: 23418444 [PubMed - indexed for MEDLINE] PMCID: PMC3572053

Breaking Up Prolonged Sitting Reduces Postprandial Glucose and Insulin Responses.

Diabetes Care. 2012 Feb 28.
Dunstan DW, Kingwell BA, Larsen R, Healy GN, Cerin E, Hamilton MT, Shaw JE, Bertovic DA, Zimmet PZ, Salmon J, Owen N.
Source
Baker IDI Heart and Diabetes Institute, Melbourne, Victoria, Australia. Abstract
OBJECTIVE
Observational studies show breaking up prolonged sitting has beneficial associations with cardi- ometabolic risk markers, but intervention studies are required to investigate causality. We exam- ined the acute effects on postprandial glucose and insulin levels of uninterrupted sitting compared with sitting interrupted by brief bouts of light- or moderate-intensity walking.

RESEARCH DESIGN AND METHODS
Overweight/obese adults (n = 19), aged 45-65 years, were recruited for a randomized three- period, three-treatment acute crossover trial: 1) uninterrupted sitting; 2) seated with 2-min bouts of light-intensity walking every 20 min; and 3) seated with 2-min bouts of moderate- intensity walking every 20 min. A standardized test drink was provided after an initial 2-h period of unin- terrupted sitting. The positive incremental area under curves (iAUC) for glucose and insulin (mean [95% CI]) for the 5 h after the test drink (75 g glucose, 50 g fat) were calculated for the respective treatments.
RESULTS
The glucose iAUC (mmol/L) ◊ h after both activity-break conditions was reduced (light: 5.2 [4.1- 6.6]; moderate: 4.9 [3.8-6.1]; both P < 0.01) compared with uninterrupted sitting (6.9 [5.5-8.7]). Insulin iAUC (pmol/ L) ◊ h was also reduced with both activity-break conditions (light: 633.6 [552.4-727.1]; moderate: 637.6 [555.5-731.9], P < 0.0001) compared with uninterrupted sitting (828.6 [722.0-950.9]).

CONCLUSIONS
Interrupting sitting time with short bouts of light- or moderate-intensity walking lowers postpran- dial glucose and insulin levels in overweight/ obese adults. This may improve glucose metabolism and potentially be an important public health and clinical intervention strategy for reducing car- diovascular risk.
PMID: 22374636

Slow postmeal walking reduces postprandial glycemia in middle- aged women. Appl Physiol Nutr Metab. 2009 Dec;34(6):1087-92.

Nygaard H, Tomten SE, Høstmark AT.

Source
Lillehammer University College, PB 952 2604 Lillehammer, Norway. havard.nygaard@hil.no Abstract
Postprandial blood glucose concentration is a risk factor for the development of cardiovascular diseases and diabetes, even at states well below hyperglycemic levels. A previous study has shown that postmeal exercise of moderate intensity blunts the blood glucose increase after carbohydrate intake (Høstmark et al. Prev. Med. 42(5): 369-371). The objective of the present study was to examine whether even postmeal slow walking would have a similar effect. Fourteen healthy women aged >50 years participated in 3 experiments in a random crossover design: after a carbo- hydrate-rich meal, either they were seated (control experiment) or they performed slow postmeal walking for 15 min (W15) or 40 min (W40). Blood glucose concentration was determined prior to the meal (fasting), and at 11 time points throughout each experiment. The W15 trial lowered the blood glucose values during walking and delayed the peak blood glucose value (p = 0.003). In W40, the postmeal blood glucose increase during walking was blunted, the peak glucose value was delayed (p = 0.001), and the incremental area under the 2-h blood glucose curve (IAUC) was reduced (p = 0.014). There was a negative relationship between IAUC and walking time (p = 0.016). The individual reducing effect of walking on IAUC correlated strongly with

[page69image15912]

IAUC on the control day (p < 0.001). We conclude that even slow postmeal walking can reduce the blood glu- cose response to a carbohydrate-rich meal. The magnitude of this effect seems to be related to the duration of walking and to the magnitude of the postprandial blood glucose response when resting after a carbohydrate-rich meal. PMID: 20029518

Objectively measured light-intensity physical activity is independently associated with 2-h plasma glucose

Healy GN, Dunstan DW, Salmon J, Cerin E, Shaw JE, Zimmet PZ, Owen N., Diabetes Care. 2007 Jun;30(6):1384-9. Epub 2007 May 1. Source
Cancer Prevention Research Centre, School of Population Health, The University of Queensland, Brisbane, Australia. g.healy@uq.edu.au

Abstract
OBJECTIVE:
We examined the associations of objectively measured sedentary time, light-intensity physical activity, and moderate- to vigorous-intensity activity with fasting and 2-h postchallenge plasma glucose in Australian adults.
RESEARCH DESIGN AND METHODS:
A total of 67 men and 106 women (mean age +/- SD 53.3 +/- 11.9 years) without diagnosed diabetes were recruited from the 2004-2005 Australian Diabetes, Obesity, and Lifestyle (AusDiab) study. Physical activity was measured by Actigraph accelerometers worn during waking hours for 7 consecutive days and summarized as sedentary time (accelerometer counts/min <100; average hours/day), light-intensity (counts/min 100-1951), and moderate- to vigorous-intensity (counts/ min > or =1,952). An oral glucose tolerance test was used to ascertain 2- h plasma glucose and fasting plasma glucose.
RESULTS:
After adjustment for confounders (including waist circumference), sedentary time was positively associated with 2-h plasma glucose (b =

[page70image14312]

0.29, 95% CI 0.11-0.48, P = 0.002); light-intensity activ- ity time (b = -0.25, -0.45 to -0.06, P = 0.012) and moderate- to vigorous-intensity activity time (b = -1.07, -1.77 to -0.37, P = 0.003) were negatively associated. Light-intensity activity remained significantly associated with 2-h plasma glucose following further adjustment for moderate- to vigorous-intensity activity (b = -0.22, -0.42 to -0.03, P = 0.023). Associations of all activity measures with fasting plasma glucose were nonsignificant (P > 0.05).

CONCLUSIONS:

These data provide the first objective evidence that light-intensity physical activity is beneficially associated with blood glucose and that sedentary time is unfavorably associated with blood glu- cose. These objective data support previous findings from studies using self-report measures, and suggest that substituting light-intensity activity for television viewing or other sedentary time may be a practical and achievable preventive strategy to reduce the risk of type 2 diabetes and cardio- vascular disease.

PMID: 17473059 http://www.ncbi.nlm.nih.gov/pubmed/17473059 Breaking Up Prolonged Sitting Reduces Postprandial Glucose and

Insulin Responses.

Dunstan DW, Kingwell BA, Larsen R, Healy GN, Cerin E, Hamilton MT, Shaw JE, Bertovic DA, Zimmet PZ, Salmon J, Owen N. Diabetes Care. 2012 Feb 28. [Epub ahead of print
Source

Baker IDI Heart and Diabetes Institute, Melbourne, Victoria, Australia.

Abstract
OBJECTIVE
Observational studies show breaking up prolonged sitting has beneficial associations with cardiometabolic risk markers, but intervention studies are required to investigate causality. We examined the acute effects on

[page71image14152]

postprandial glucose and insulin levels of uninterrupted sitting compared with sitting interrupted by brief bouts of light- or moderate-intensity walking.
RESEARCH DESIGN AND METHODS

Overweight/obese adults (n = 19), aged 45-65 years, were recruited for a randomized three- period, three-treatment acute crossover trial: 1) uninterrupted sitting; 2) seated with 2-min bouts of light-intensity walking every 20 min; and 3) seated with 2-min bouts of moderate- intensity walking every 20 min. A standardized test drink was provided after an initial 2-h period of unin- terrupted sitting. The positive incremental area under curves (iAUC) for glucose and insulin (mean [95% CI]) for the 5 h after the test drink (75 g glucose, 50 g fat) were calculated for the respective treatments.

RESULTS
The glucose iAUC (mmol/L) ◊ h after both activity-break conditions was reduced (light: 5.2 [4.1- 6.6]; moderate: 4.9 [3.8-6.1]; both P < 0.01) compared with uninterrupted sitting (6.9 [5.5-8.7]). Insulin iAUC (pmol/ L) ◊ h was also reduced with both activity-break conditions (light: 633.6 [552.4-727.1]; moderate: 637.6 [555.5-731.9], P < 0.0001) compared with uninterrupted sitting (828.6 [722.0-950.9]).
CONCLUSIONS
Interrupting sitting time with short bouts of light- or moderate-intensity walking lowers postpran- dial glucose and insulin levels in overweight/ obese adults. This may improve glucose metabolism and potentially be an important public health and clinical intervention strategy for reducing cardiovascular risk.
PMID: 22374636

Self-reported sitting time and markers of inflammation, insulin resistance, and adiposity.

Am J Prev Med. 2012 Jan;42(1):1-7.
Yates T, Khunti K, Wilmot EG, Brady E, Webb D, Srinivasan B, Henson J, Talbot D, Davies MJ. Source

Department of Cardiovascular Sciences, University of Leicester, Leicester, United Kingdom. ty20@le.ac.uk
Abstract
BACKGROUND:

Sedentary behavior is emerging as an independent risk factor for chronic disease; however, poten- tial mechanisms underpinning these observations are not well understood.
PURPOSE:

This study aimed to investigate the association of self-reported weekday sitting time with biomar- kers linked to chronic low-grade inflammation, insulin resistance, and adiposity.
METHODS:

This study reports data from individuals attending a diabetes screening program, United King- dom, 2004-2007; analysis was conducted in 2010. Sitting time and physical activity were mea- sured using the International Physical Activity Questionnaire; biochemical outcomes included fasting and 2-hour postchallenge glucose, fasting insulin, C- reactive protein (CRP), leptin, adi- ponectin, and interleukin-6 (IL-6).

RESULTS:
This study included 505 (female=46%; South-Asian ethnicity=19%, aged 59±10 years, BMI=29.5±4.7) individuals with valid sitting data. Increased sitting time was positively associ- ated with fasting insulin, leptin, leptin/adiponectin ratio, CRP, and IL-6 in women, but not men, after adjustment for age, ethnicity, social deprivation, and smoking and medication status; interaction analysis revealed that the gender-specific differences were significant. The associations for women remained significant after additional adjustment for total moderate- to vigorous- intensity physical activity; however all associations were attenuated when further adjusted for BMI. There was no association between sitting time and glycemic status.
CONCLUSIONS:
Total self-reported weekday sitting time was associated with biomarkers linked to chronic low- grade inflammation and poor metabolic health in

[page73image14048]

women, but not men, independent of physical activity.
Copyright © 2012 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

Sedentary behavior and adiposity-associated inflammation: the Multi-Ethnic Study of Atherosclerosis. Am J Prev Med. 2012 Jan; 42(1):8-13.
Allison MA, Jensky NE, Marshall SJ, Bertoni AG, Cushman M. Source

Department of Family and Preventive Medicine, University of California San Diego, La Jolla, California 92093-0965, USA. mallison@ucsd.edu Abstract
BACKGROUND:

Sedentary behavior is associated with adiposity and cardiometabolic risk.
PURPOSE:
To determine the associations between sedentary behavior and measures of adiposity-associated inflammation.

METHODS:
Between 2002 and 2005, a total of 1543 Multi-Ethnic Study of Atherosclerosis participants com- pleted detailed health history questionnaires, underwent physical measurements, and had blood assayed for adiponectin, leptin, tumor necrosis factor-alpha (TNF-?) and resistin. Analyses included linear regression completed in 2010. The mean age was 64.3 years and nearly 50% were female. Forty-one percent were non-Hispanic white, 24% Hispanic-American, 20% African- American, and 14% Chinese-American.
RESULTS:
In linear regression analyses and with adjustment for age, gender, ethnicity, education, BMI, smoking, alcohol consumption, hypertension, diabetes mellitus, dyslipidemia, hormone therapy and waist circumference, sedentary behavior was associated with higher natural log ("ln") of lep- tin and ln TNF-? but a lower ln adiponectin-to-leptin

[page74image12824]

ratio (?=0.07, ?=0.03 and -0.07, p<0.05 for all). Compared to the first tertile, and after the same adjustment, the second and third tertiles of sedentary behavior were associated with higher levels of ln leptin (? =0.11 and ?=0.12, respec- tively; p<0.05 for both) but lower levels of the adiponectin-to-leptin ratio (?=-0.09 and -0.11, respectively; p<0.05 for both).

CONCLUSIONS:
Sedentary behavior is associated with unfavorable levels of adiposity- associated inflammation. Copyright © 2012 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved. PMID: 22176840

Forest bathing

Forest bathing

Eur J Appl Physiol. 2011 Nov;111(11):2845-53. Epub 2011 Mar 23. Acute effects of walking in forest environments on cardiovascular and metabolic parameters.
Li Q, Otsuka T, Kobayashi M, Wakayama Y, Inagaki H, Katsumata M, Hirata Y, Li Y, Hirata K, Shimizu T, Suzuki H, Kawada T, Kagawa T. Source

Department of Hygiene and Public Health, Nippon Medical School, 1-1-5 Sendagi, Bunkyo-ku, Tokyo, 113-8602, Japan. qing-li@nms.ac.jp Abstract
We previously found that forest environments reduced stress hormones such as adrenaline and noradrenaline and showed the relaxing effect both in male and female subjects. In the present study, we investigated the effects of walking under forest environments on cardiovascular and metabolic parameters. Sixteen healthy male subjects (mean age 57.4 ± 11.6 years) were selected after obtaining informed consent. The subjects took day trips to a forest park in the suburbs of Tokyo and to an urban area of Tokyo as a control in September 2010. On both trips, they walked for 2 h in the morning and afternoon on a Sunday. Blood and

[page75image15032]

urine were sampled on the morning before each trip and after each trip. Blood pressure was measured on the morning (0800) before each trip, at noon (1300), in the afternoon (1600) during each trip, and on the morning (0800) after each trip. The day trip to the forest park significantly reduced blood pressure and urinary noradrenaline and dopamine levels and significantly increased serum adiponectin and dehydroepi- androsterone sulfate (DHEA-S) levels. Walking exercise also reduced the levels of serum N-ter- minal pro-B-type natriuretic peptide (NT-proBNP) and urinary dopamine. Taken together, habitual walking in forest environments may lower blood pressure by reducing sympathetic nerve activity and have beneficial effects on blood adiponectin and DHEA-S levels, and habitual walk- ing exercise may have beneficial effects on blood NT-proBNP levels.

PMID: 21431424

Therapeutic effect of forest bathing on human hypertension in the elderly.

Mao GX1, Cao YB, Lan XG, He ZH, Chen ZM, Wang YZ, Hu XL, Lv YD, Wang GF, Yan J.

Author information

1Zhejiang Provincial Key Laboratory of Geriatrics & Geriatrics Institute of Zhejiang Province, Zhejiang Hospital, Hangzhou 310013, Zhejiang Province, PR China
Abstract

OBJECTIVE:

To provide scientific evidence supporting the efficacy of forest bathing as a natural therapy for human hypertension.

METHODS:

Twenty-four elderly patients with essential hypertension were randomly divided into two groups of 12. One group was sent to a broad-leaved evergreen forest to experience a 7-day/7-night trip, and the other was sent to a city area in Hangzhou for control. Blood pressure indicators, cardiovascular disease-related pathological factors including endothelin-1, homocysteine,

[page76image15344] [page76image15504] [page76image15664] [page76image15824] [page76image15984] [page76image16144] [page76image16304] [page76image16464] [page76image16624] [page76image16784] [page76image16944]

renin, angiotensinogen, angiotensin II, angiotensin II type 1 receptor, angiotensin II type 2 receptor as well as inflammatory cytokines interleukin-6 and tumor necrosis factor α were detected. Meanwhile, profile of mood states (POMS) evaluation was used to assess the change of mood state of subjects. In addition, the air quality in the two experimental sites was monitored during the 7-day duration, simultaneously.

RESULTS:

The baselines of the indicators of the subjects were not significantly different. Little alteration in the detected indicators in the city group was observed after the experiment. While subjects exposed to the forest environment showed a significant reduction in blood pressure in comparison to that of the city group. The values for the bio-indicators in subjects exposed to the forest environment were also lower than those in the urban control group and the baseline levels of themselves. POMS evaluation showed that the scores in the negative subscales were lowered after exposure to the forest environment. Besides, the air quality in the forest environment was much better than that of the urban area evidenced by the quantitative detection of negative ions and PM10 (particulate matter < 10 μm in aerodynamic diameter).

CONCLUSION:

Our results provided direct evidence that forest bathing has therapeutic effects on human hypertension and induces inhibition of the renin- angiotensin system and inflammation, and thus inspiring its preventive efficacy against cardiovascular disorders.

Copyright © 2012 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.

PMID: 22948092

Effects of short-term forest bathing on human health in a broad-leaved evergreen forest in Zhejiang Province, China.

Mao GX1, Lan XG, Cao YB, Chen ZM, He ZH, Lv YD, Wang YZ, Hu XL, Wang GF, Yan J. Biomed Environ Sci. 2012 Jun;25(3):317-24. doi:

10.3967/0895-3988.2012.03.010.

Abstract

OBJECTIVE:

[page77image17160] [page77image17320] [page77image17480] [page77image17640] [page77image17800] [page77image17960] [page77image18120] [page77image18280] [page77image18440] [page77image18600] [page77image18760] [page77image18920]

To investigate the effects of short-term forest bathing on human health.

METHODS:

Twenty healthy male university students participated as subjects and were randomly divided into two groups of 10. One group was sent on a two-night trip to a broad-leaved evergreen forest, and the other was sent to a city area. Serum cytokine levels reflecting inflammatory and stress response, indicators reflecting oxidative stress, the distribution of leukocyte subsets, and plasma endothelin-1 (ET-1) concentrations were measured before and after the experiment to evaluate the positive health effects of forest environments. A profile of mood states (POMS) evaluation was used to assess changes in mood states.

RESULTS:

No significant differences in the baseline values of the indicators were observed between the two groups before the experiment. Subjects exposed to the forest environment showed reduced oxidative stress and pro- inflammatory level, as evidenced by decreased malondialdehyde, interleukin-6, and tumor necrosis factor a levels compared with the urban group. Serum cortisol levels were also lower than in the urban group. Notably, the concentration of plasma ET-1 was much lower in subjects exposed to the forest environment. The POMS evaluation showed that after exposure to the forest environment, subjects had lower scores in the negative subscales, and the score for vigor was increased.

CONCLUSION:
Forest bathing is beneficial to human health, perhaps through preventive effects related to several pathological factors.

Copyright © 2012 The Editorial Board of Biomedical and Environmental Sciences. Published by Elsevier B.V. All rights reserved.

Eur J Appl Physiol. 2011 Nov;111(11):2845-53. Epub 2011 Mar 23. Acute effects of walking in forest environments on cardiovascular and metabolic parameters.
Li Q, Otsuka T, Kobayashi M, Wakayama Y, Inagaki H, Katsumata M, Hirata Y, Li Y, Hirata K, Shimizu T, Suzuki H, Kawada T, Kagawa T.

Source
Department of Hygiene and Public Health, Nippon Medical School, 1-1-5 Sendagi, Bunkyo-ku, Tokyo, 113-8602, Japan. qing-li@nms.ac.jp Abstract
We previously found that forest environments reduced stress hormones such as adrenaline and noradrenaline and showed the relaxing effect both in male and female subjects. In the present study, we investigated the effects of walking under forest environments on cardiovascular and metabolic parameters. Sixteen healthy male subjects (mean age 57.4 ± 11.6 years) were selected after obtaining informed consent. The subjects took day trips to a forest park in the suburbs of Tokyo and to an urban area of Tokyo as a control in September 2010. On both trips, they walked for 2 h in the morning and afternoon on a Sunday. Blood and urine were sampled on the morning before each trip and after each trip. Blood pressure was measured on the morning (0800) before each trip, at noon (1300), in the afternoon (1600) during each trip, and on the morning (0800) after each trip. The day trip to the forest park significantly reduced blood pressure and urinary noradrenaline and dopamine levels and significantly increased serum adiponectin and dehydroepi- androsterone sulfate (DHEA-S) levels. Walking exercise also reduced the levels of serum N-ter- minal pro-B-type natriuretic peptide (NT-proBNP) and urinary dopamine. Taken together, habitual walking in forest environments may lower blood pressure by reducing sympathetic nerve activity and have beneficial effects on blood adiponectin and DHEA-S levels, and habitual walk- ing exercise may have beneficial effects on blood NT-proBNP levels.

PMID: 21431424

Lipoprotein Lipase

AuthorsMead JR, et al. Show all Journal
J Mol Med (Berl). 2002 Dec;80(12):753-69. Epub 2002 Oct 24. Affiliation
Cardiff School of Biosciences, Cardiff University, Museum Avenue, P.O.

[page79image15672]

Box 911, Cardiff CF10 3US, Wales, UK. Abstract

Lipoprotein lipase (LPL) catalyses the hydrolysis of the triacylglycerol component of circulating chylomicrons and very low density lipoproteins, thereby providing non-esterified fatty acids and 2- monoacylglycerol for tissue utilisation. Research carried out over the past two decades have not only established a central role for LPL in the overall lipid metabolism and transport but have also identified additional, non-catalytic functions of the enzyme. Furthermore, abnormalities in LPL function have been found to be associated with a number of pathophysiological conditions, including atherosclerosis, chylomicronaemia, obesity, Alzheimer’s disease, and dyslipidaemia associated with diabetes, insulin resistance, and infection. Advances have also been made in relating the various domains in the protein to different functions, and in understanding the mechanisms that are responsible for the changes in LPL expression seen in response to nutri- tional and other physiological changes, and during disease. This review summarises recent findings in relation to the structure, function, and regulation of LPL along with its important role in disease.

PMID 12483461

Longevity

Sedentary behaviour and life expectancy in the USA: a cause- deleted life table analysis

1.Peter T Katzmarzyk1, I-Min Lee2, BMJ Open 2012;2:e000828 doi: 10.1136/bmjopen-2012- 000828 / July 10, 2012
Abstract
Objectives To determine the impact of sitting and television viewing on life expectancy in the USA.

Design Prevalence-based cause-deleted life table analysis.
Setting Summary RRs of all-cause mortality associated with sitting and

television viewing were obtained from a meta-analysis of available prospective cohort studies. Prevalences of sitting and television viewing were obtained from the US National Health and Nutrition Examination Survey. Primary outcome measure Life expectancy at birth.

Results The estimated gains in life expectancy in the US population were 2.00?years for reducing excessive sitting to <3?h/day and a gain of 1.38?years from reducing excessive television viewing to <2?h/day. The lower and upper limits from a sensitivity analysis that involved simultaneously varying the estimates of RR (using the upper and lower bounds of the 95% CI) and the prevalence of television viewing (±20%) were 1.39 and 2.69?years for sitting and 0.48 and 2.51?years for television viewing, respectively.

Conclusion Reducing sedentary behaviours such as sitting and television viewing may have the potential to increase life expectancy in the USA. http://bmjopen.bmj.com/content/2/4/e000828.abstract

Sedentary Behavior and Mortality in Older Women: The Women’s

Health Initiative, February 2014, American Journal of Preventive Medicine Vol. 46, No. 2

Analyzing self-reported data about sitting habits gathered from 92,234 women during the Women’s Health Initiative Observational Study from 1993-1998, Cornell nutritionist Dr. Rebecca Seguin et. al. found the effects twelve years later. Sedentary time was assessed in four categories <4, >4–8, >8–11, >11 hours. Odds for premature mortality increased by 12% for women who sat more than 11 hours a day compared to those who sat for 4 “hours. Odds for death by cardiovascular disorder increased by 15%, death by coronary heart disease by 27% and cancer by 17%.

Television viewing time independently predicts all-cause and cardiovascular mortality: the EPIC Norfolk Study Cardiol. 2012 Dec; 60(6):495-502. doi: 10.1016/j.jjcc.2012.08.003. Epub 2012 Sep 1.

[page81image15416] [page81image15576] [page81image15736] [page81image15896] [page81image16056] [page81image16216]

1.Katrien Wijndaele1, Søren Brage1, Hervé Besson1, Kay-Tee Khaw2, Stephen J Sharp1, Robert Luben2, Nicholas J Wareham1 and Ulf Ekelund1,*
Author Affiliations

1.1MRC Epidemiology Unit, Cambridge, UK and 2Department of Public Health and Primary Care, Institute of Public Health, University of Cambridge, Cambridge, UK

Corresponding author. MRC Epidemiology Unit, Institute of Metabolic Science, Box 285, Addenbrooke’s Hospital, Hills Road, Cambridge CB2 0QQ, UK. E-mail: ulf.ekelund@mrc- epid.cam.ac.uk
Accepted May 20, 2010., •International Journal of Epidemiology

Abstract
Background Television viewing (TV), a highly prevalent behaviour, is associated with higher car- diovascular risk independently of physical activity. The relationship with mortality, however, is relatively unknown.

Methods
We examined the prospective relationship between TV time and all- cause, cardiovascular and cancer mortality in a population-based cohort [The European Prospective Investigation into Can- cer and Nutrition (EPIC), Norfolk] of 13,197 men and women {age [SD (standard deviation)]: 61.5?±?9.0 years}. Participants were free from stroke, myocardial infarction and cancer at base- line in 1998–2000 and were followed up for death ascertainment until 2009 (9.5?±?1.6 years). TV time, total physical activity energy expenditure (PAEE), education level, smoking status, alcohol consumption, anti-hypertensive and lipid- lowering medication use, participant and family history of disease and total energy intake were self-reported; height and weight were measured by standardized procedures. Hazard ratios (HRs) [95% confidence interval (CI)] for mortality were estimated per 1-h/day increase in TV.

Results
Each 1-h/day increase in TV time was associated with increased hazard

of all-cause (HR?=?1.04, 95% CI?=?1.01–1.09; 1270 deaths) and cardiovascular (HR?=?1.07, 95% CI?=?1.01–1.15; 373 deaths), but not cancer mortality (HR?=?1.04, 95% CI?=?0.98–1.10; 570 deaths). This was inde- pendent of gender, age, education, smoking, alcohol, medication, diabetes history, family history of cardiovascular disease and cancer, body mass index (BMI) and PAEE. They were similar when stratified by gender, age, education, BMI and PAEE. The population- attributable fraction for all- cause mortality comparing the highest TV tertile (>3.6?h/day) with the lowest (<2.5?h/day) was 5.4%.

Conclusions These findings suggest that public health recommendations should consider advising a reduction in TV time, a predominant leisure activity in modern society, in addition to advocating physical activity.

Metabolic Syndrome

Sedentary behaviors, physical activity, and metabolic syndrome in middle-aged French sub- jects.

Bertrais S, Beyeme-Ondoua JP, Czernichow S, Galan P, Hercberg S, Oppert JM., Obes Res. 2005 May;13(5):936-44.
UMR INSERM U557/INRA U1125/CNAM EA 3200-MR, 5 rue du Vertbois, F-75003 Paris, France. sandrine.bertrais@cnam.fr

OBJECTIVE:
To study the relationships of time spent in sedentary occupations with the National Cholesterol Education Program-defined metabolic syndrome (MS), taking into account the habitual level of physical activity (PA).

49

RESEARCH METHODS AND PROCEDURES:
This was a cross-sectional analysis in 1902 men and 1932 women 50 to

69 years of age participat- ing in the French Supplementation with Antioxidant Vitamins and Minerals study. We assessed past-year PA, television watching or computer use, and reading during leisure with the Modifiable Activity Questionnaire. Subjects who performed at least 150 min/wk of moderate-intensity PA (3 to 6 metabolic equivalent tasks) or 60 min/wk of vigorous PA (>6 metabolic equivalent tasks) were considered as meeting recommended levels.

RESULTS:
The frequency of most MS components increased with time spent in front of a screen and decreased with increasing PA levels. The likelihood to have MS, adjusted for age, education, and smoking, was decreased by one-third in subjects meeting moderate PA guidelines and by two- thirds in subjects meeting vigorous PA recommendations [odds ratio (95% CI), 0.34 (0.17 to 0.66) in women, 0.44 (0.28 to 0.68) in men] compared with those with insufficient PA. Independently of PA levels, time spent in front of a screen was positively associated with the likelihood to have the MS in women [odds ratio (95% CI), 3.30 (2.04 to 5.34)], whereas in both sexes, no association was found with time spent reading. DISCUSSION:
The relationship of the MS with a sedentary lifestyle differs according to sex and type of seden- tary occupation. These results suggest the need to assess selected indicators of sedentary behavior in preventive programs. PMID: 15919848; http://www.ncbi.nlm.nih.gov/pubmed/15919848? dopt=AbstractPlus&hold- ing=f1000,f1000m,isrctn

Accelerometer-determined moderate intensity lifestyle activity and cardiometabolic health.

Camhi SM, Sisson SB, Johnson WD, Katzmarzyk PT, Tudor-Locke C. Prev Med. 2011 May 1;52(5):358-60. Epub 2011 Feb 16.
Source
Pennington Biomedical Research Center, 6400 Perkins Road, Baton Rouge, LA, USA. sarah.camhi@umb.edu

[page84image14968]

Abstract
OBJECTIVE:
Objective To assess the relationship between moderate intensity lifestyle activity (LA) and cardi- ometabolic health using accelerometer data from the National Health and Nutrition Examination Survey (NHANES) 2005-2006.
METHODS:
One thousand three hundred and seventy-one adults (50% men; 71% non-Hispanic white) pro- vided valid data to quantify time in LA [760-2019 counts per minute (CPM)] and moderate-to- vigorous physical activity (MVPA; ≥ 2020 CPM). Associations between LA [minutes per day (min/day); steps per day (steps/day)], and cardiometabolic risk factors [triglycerides, HDL-cho- lesterol (HDL-C), blood pressure, glucose, waist circumference], metabolic syndrome, self- reported hypertension and diabetes were investigated using logistic regression. Analyses were adjusted for age, gender, race/ethnicity, and MVPA categories.
RESULTS:
Greater time in lifestyle activity LA (min/day), independent from moderate-to-vigorous physical activity MVPA, was associated with lower odds of elevated triglycerides (OR, 95% CI per 30 LA minutes: 0.89,0.83-0.97), low HDL-C (0.87,0.83-0.92), elevated waist circumference (0.88,0.83- 0.94), metabolic syndrome (0.87,0.80-0.96), and diabetes (0.67,0.55-0.82). The same cardiometa- bolic risk factors were also significantly associated with LA steps/day. No significant association was found between LA (min/day or steps/day) and glucose or blood pressure.
CONCLUSION:
Accumulation of time or steps in LA is independently related to lower odds for certain cardiomet- abolic risk factors. Research should consider the effects of increasing LA, which could influence future physical activity recommendations.
Copyright © 2011 Elsevier Inc. All rights reserved.
PMID: 21300082 [PubMed

Associations of TV viewing and physical activity with the metabolic syndrome in Australian adults.

Diabetologia. 2005 Nov;48(11):2254-61. Epub 2005 Oct 7.
Dunstan DW, Salmon J, Owen N, Armstrong T, Zimmet PZ, Welborn TA, Cameron AJ, Dwyer T, Jolley D, Shaw JE; AusDiab Steering Committee.
Source
International Diabetes Institute, Melbourne, Victoria, Australia. ddunstan@idi.org.au
Abstract
AIMS/HYPOTHESIS:
We analysed a sample of Australian adults to determine the strength of associations of TV view- ing and participation in physical activity with the metabolic syndrome.
METHODS:
This population-based cross-sectional study included 6,241 adults aged > or =35 years who were free from diagnosed diabetes mellitus and self- reported ischaemic disease and were not taking lipid-lowering or antihypertensive drugs. The metabolic syndrome was defined according to the 1999 World Health Organization criteria. Participants self-reported TV viewing time and physical activity time for the previous week. RESULTS:
The adjusted odds ratio of having the metabolic syndrome was 2.07 (95% CI 1.49-2.88) in women and 1.48 (95% CI 0.95-2.31) in men who watched TV for >14 h per week compared with those who watched < or =7.0 h per week. Compared with those who were less active (<2.5 h per week), the odds ratio for the metabolic syndrome was 0.72 (95% CI 0.58-0.90) in men and 0.53 (95% CI 0.38-0.74) in women who were active (> or =2.5 h per week). Longer TV viewing (>14 h per week) was associated with an increased risk of insulin resistance, obesity and dyslipidaemia in both men and women. A total physical activity time of > or =2.5 h per week was associated with a reduced prevalence of both insulin resistance and dyslipidaemia in both sexes and reduced preva-

[page86image15472]

lence of both obesity and hypertension in women. CONCLUSIONS/INTERPRETATION:

Increased TV viewing time was associated with an increased prevalence of the metabolic syndrome, while physical activity was associated with a reduced prevalence. Population strategies addressing the metabolic syndrome should focus on reducing sedentary behaviours such as TV viewing, as well as increasing physical activity.

PMID: 16211373 (http://www.ncbi.nlm.nih.gov/pubmed/16211373)

Joint Association of Sitting Time and Physical Activity with Metabolic Risk Factors among Middle-Aged Malays in a Developing Country: A Cross-Sectional Study.

PLoS One. 2013 Apr 17;8(4):e61723. doi: 10.1371/journal.pone. 0061723. Print 2013.Chu AH, Moy FM.
Julius Centre University of Malaya, Department of Social and Preventive Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia.

Abstract BACKGROUND:

Prolonged sitting is associated with increased weight and higher risks for abdominal obesity, dys- lipidaemia, hyperglycaemia and hypertension among the adult population. This has been well documented in the West, but studies on these associations are lacking in developing countries, including Malaysia.

OBJECTIVE:
This cross-sectional study aimed to examine the joint association of sitting time and physical activity with metabolic risk factors among middle-aged working adults.
METHODOLOGY:
A total of 686 Malay men and women participated (mean age 45.9±6.5 years). Metabolic syndrome was diagnosed from the modified NCEP

[page87image12728]

ATP III criteria. Self-reported sitting time was obtained with the validated Malay version of the International Physical Activity Questionnaire. Participants were asked about their time spent sitting during travel in a motor vehicle, e.g., car, motorcycle or bus, over the preceding 7 days. Logistic regression was used to estimate the odds ratio with the confidence interval for the combined effects of sitting quartiles and physical activity categories with metabolic risk factors. RESULTSSIGNIFICANCE: The prevalence of metabolic syndrome among our participants was 31.9%. Their average total sitting time (including transpor- tation) was 7.6±2.4 h/day. After we adjusted for gender and educational level, higher sitting quartiles and physically inactive groups were associated with higher odds for metabolic syndrome compared with the referent group (sitting <6 h/day and physically active). In the physically active stratum, the odds for metabolic syndrome in participants who sat ≥9.3 h/day was 3.8 times that of participants who sat <6 h/day. Both higher sitting quartiles and insufficient physi- cal activity were associated with adverse effects on abdominal obesity, hypertriglyceridemia and hyperglycaemia. CONCLUSION:

In joint analyses of sitting time and physical activity, higher sitting time and insufficient physical activity were deleteriously associated with odds for metabolic risk factors in middle-aged Malay men and women. PMID: 23613917

Full article available: http://www.ncbi.nlm.nih.gov/pmc/articles/ PMC3629118/

Association between television viewing and the risk of metabolic syndrome in a community- based population

Pei-Chia Chang1 , Tsai-Chung Li2,3,4,5 , Ming-Tsang Wu6 , Chiu- Shong Liu7,8 , Chia-Ing Li2 , Ching-Chu Chen7,8 , Wen-Yuan Lin7,8 , Shin-Yuh Yang3 and Cheng-Chieh Lin2,5,7,8,9
1 Administration Center, China Medical University Hospital, Taichung, Taiwan

[page88image15152] [page88image15312]

2 Department of Medical Research, China Medical University Hospital, Taichung, Taiwan

3 Graduate Institute of Chinese Medicine Science, College of Chinese Medicine, China Medical University, Taichung, Taiwan
4 Biostatistics Center, China Medical University, Taichung, Taiwan
5 Institute of Health Care Administration, College of Health Science, Asia University, Taichung, Taiwan

6 Graduate Institute of Occupational Safety and Health, Kaohsiung Medical University, Taiwan 7 Department of Family Medicine, China Medical University Hospital, Taichung, Taiwan
8 Department of Family Medicine, College of Medicine, China Medical University, Taichung, Taiwan

9 School and Graduate Institute of Health Care Administration, College of Public Health, China Medical University, Taichung, Taiwan

author email corresponding author email
BMC Public Health 2008, 8:193doi:10.1186/1471-2458-8-193
The electronic version of this article is the complete one and can be found online at: http:// www.biomedcentral.com/1471-2458/8/193
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/ licenses/by/2.0), which permits unrestricted use, distribu- tion, and reproduction in any medium, provided the original work is properly cited.
Abstract
Background
As a result of metabolic syndrome becoming an important issue during recent decades, many studies have explored the risk factors contributing to its development. However, less attention has been paid to the risk associated with sedentary behavior, especially television viewing. This study examined the association between television viewing time and the

[page89image13232] [page89image13392] [page89image13552]

risk of having metabolic syn- drome in a population of Taiwanese subjects.

Methods
This community-based cross-sectional study included 2,353 subjects (1,144 men and 1,209 women) aged 40 and over from October, 2004 to September, 2005. Information about the time spent watching TV was obtained using a self-administered questionnaire. The definition of meta- bolic syndrome was according to the Third Report of the National Cholesterol Education Pro- gram's Adult Treatment Panel modified for Asians.

Results
Compared to subjects who viewed TV < 14 hr/week, those who viewed TV > 20 hr/week had a 1.50-fold (95% confidence intervals (CI): 1.10, 2.03) risk for men and a 1.93-fold (95% CI: 1.37, 2.71) risk for women of having metabolic syndrome, after adjusting for physical activity and other covariates. Stratifying by the three categories of total activity levels, TV viewing time > 20 hr/ week was found to still hold a significant risk for having metabolic syndrome in the lowest of the three categories of total activity level for men and in all three categories of total activity level for women.

Conclusion
The findings suggest that TV viewing is an independent risk factor associated with metabolic syndrome in Taiwanese people.

Leisure Time Sedentary Behavior, Occupational/Domestic Physical Activity, and Metabolic Syndrome in U.S. Men and Women

Metab Syndr Relat Disord. 2009 December; 7(6): 529–536. doi: 10.1089/met.2009.0023 PMCID: PMC2796695 NIHMSID: NIHMS132193
Copyright © Mary Ann Liebert, Inc.

Susan B. Sisson, Ph.D., Sarah M. Camhi, Ph.D., Timothy S. Church,

M.D., M.P.H., Ph.D., Corby K. Martin, Ph.D., Catrine Tudor-Locke, Ph.D., Claude Bouchard, Ph.D., Conrad P. Earnest, Ph.D., Steven R. Smith, M.D., Robert L. Newton, Jr., M.D., Tuomo Rankinen, Ph.D., and Peter T. Katz- marzyk, Ph.D.

Susan B. Sisson, Ph.D., Pennington Biomedical Research Center, Baton Rouge, Louisiana. Contributor Information.
Address correspondence to: Peter T. Katzmarzyk, Ph.D., Pennington Biomedical Research Center, 6400 Perkins Road, Baton Rouge, LA 70808. E-mail:peter.katzmarzyk@pbrc.edu

This article has been cited by other articles in PMC. • Other Sections? Abstract
Background

This study examines leisure time sedentary behavior (LTSB) and usual occupational/domestic activity (UODA) and their relationship with metabolic syndrome and individual cardiovascular disease (CVD) risk factors, independent of physical activity level.

Methods

National Health and Nutrition Examination Survey (NHANES) 2003– 2006 data from men (n = 1868) and women (n = 1688) with fasting measures were classified as having metabolic syndrome by the American Heart Association/National Heart, Lung, and Blood Institute (AHA/ NHLBI) def- inition. LTSB was determined from self-reported television viewing and computer usage. UODA was self-reported daily behavior (sitting, standing, walking, carrying loads).

Results
LTSB ≥4 hours/day was associated with odds of having metabolic syndrome of 1.94 (95% confi- dence interval [CI], 1.24, 3.03) in men compared to ≤1 hour/day. LTSB ≥4 hour/day was also associated with higher odds of elevated waist circumference (1.88, CI, 1.03, 3.41), low high-den- sity lipoprotein cholesterol (HDL-C) (1.84, CI, 1.35, 2.51),

[page91image13880]

and high blood pressure (1.55, CI, 1.07, 2.24) in men. LTSB 2–3 hours/ day was associated with higher odds of elevated glucose (1.32, CI, 1.00, 1.75) in men. In women, odds of metabolic syndrome were 1.54 (CI, 1.00, 2.37) with ≥4 hours/day LTSB, but LTSB was not associated with risk of the individual CVD risk fac- tors. Higher LTSB was associated with metabolic syndrome in inactive men (1.50, CI, 1.07, 2.09), active men (1.74, CI, 1.11, 2.71), inactive women (1.69, CI, 1.24, 2.33), but not active women (1.62, CI, 0.87,3.01). UODA was not strongly associated with metabolic syndrome or CVD risk factors in either men or women. Conclusions

in men, high ltsb is associated with higher odds of metabolic syndrome and individual cvd risk factors regardless of meeting physical activity recommendations. in women, high ltsb is associ- ated with higher odds of metabolic syndrome only in those not meeting the physical activity recommendations.

Associations Between Television Viewing Time and Overall Sitting Time with the Metabolic Syndrome in Older Men and Women: The Australian Diabetes Obesity and Lifestyle Study

1.Paul A. Gardiner BSc (Hons)1, Genevieve N. Healy PhD1,2, Elizabeth G. Eakin PhD1,2, Bron- wyn K. Clark MPH1, David W. Dunstan PhD1,2,3,4,5, Jonathan E. Shaw MD2, Paul Z. Zimmet MD2, Neville Owen PhD1,2

Article first published online: 13 MAY 2011

DOI: 10.1111/j.1532-5415.2011.03390.x
© 2011, Copyright the Authors. Journal compilation © 2011, The American Geriatrics Society Journal of the American Geriatrics Society Volume 59, Issue 5, pages 788–796, May 2011

OBJECTIVES: To examine associations between self-reported television (TV) viewing time and overall sitting time with the metabolic syndrome

[page92image15144] [page92image15312]

and its components.
DESIGN: Cross-sectional.
SETTING: Population-based sample of older men and women living in Australia. PARTICIPANTS: One thousand nine hundred fifty-eight participants from the Australian Diabe- tes, Obesity and Lifestyle (AusDiab) study (aged≥60, mean age 69, 54% women). MEASUREMENTS: Self-reported television viewing time and overall sitting time were collected using an interviewer-administered questionnaire. The metabolic syndrome was defined according to the revised International Diabetes Federation criteria.

RESULTS: Compared with those in the lowest quartile, the odds ratios (ORs) of the metabolic syndrome in the highest quartile of television viewing time were 1.42 (95% confidence interval (CI)=0.93–2.15) for men and 1.42 (95% CI=1.01–2.01) for women and in the highest quartile of overall sitting time were 1.57 (95% CI=1.02–2.41) for men and 1.56 (95% CI=1.09–2.24) for women. Television viewing time was associated with lower high-density lipoprotein cholesterol (HDL-C) levels and glucose intolerance in women. Overall sitting time was detrimentally associ- ated with greater risk of high triglyceride levels in men and women, abdominal obesity in women, and low HDL-C levels in men. All models were adjusted for age, education, physical activity, self- rated health, employment, diet, smoking, and alcohol intake and for hormone replacement therapy and estrogen use in women.

CONCLUSION: For older adults, high levels of sedentary behavior were associated with greater prevalence of the metabolic syndrome; reducing prolonged overall sitting time may be a feasible way to improve metabolic health. (http://onlinelibrary.wiley.com/doi/10.1111/j. 1532- 5415.2011.03390.x/full)

Microbreaks

Appl Ergon. 2001 Jun;32(3):225-37.
Computer terminal work and the benefit of microbreaks.

[page93image14408] [page93image14568]

Mclean L, Tingley M, Scott RN, Rickards J.
Source: School of Physiotherapy, Dalhousie University, Halifax, NS, Canada. linda.mclean@dal.ca
Abstract
Microbreaks are scheduled rest breaks taken to prevent the onset or progression of cumulative trauma disorders in the computerized workstation environment. The authors examined the benefit of microbreaks by investigating myoelectric signal (MES) behavior, perceived discomfort, and worker productivity while individuals performed their usual keying work. Participants were randomly assigned to one of three experimental groups. Each participant provided data from working sessions where they took no breaks, and from working sessions where they took breaks according to their group assignment: microbreaks at their own discretion (control), microbreaks at 20 min intervals, and microbreaks at 40 min intervals. Four main muscle areas were studied: the cervical extensors, the lumbar erector spinae, the upper trapezius/supraspinatus, and the wrist and finger extensors. The authors have previously shown that when computer workers remained seated at their workstation, the muscles performing sustained postural contractions displayed a cyclic trend in the mean frequency (MNF) of the MES (McLean et al., J. Electrophysiol. Kinesiol. 10 (1) (2000) 33). The data provided evidence (p < 0.05) that all microbreak protocols were associated with a higher frequency of MNF cycling at the wrist extensors, at the neck when microbreaks were taken by the control and 40 min protocol groups, and at the back when breaks were taken by the 20 and 40 min protocol groups. No significant change in the frequency of MNF cycling was noted at the shoulder. It was determined (p < 0.05) that microbreaks had a positive effect on reducing discomfort in all areas studied (Four main muscle areas were studied: the cervical extensors, the lumbar erector spinae, the upper trapezius/supraspinatus, and the wrist and finger extensors.) during computer terminal work, particularly when breaks were taken at 20 min intervals. Finally, microbreaks showed no evidence of a detrimental effect on worker productivity. The underlying

[page94image17000]

cause of MNF cycling, and its relationship to the development of discomfort or cumulative trauma disorders remains to be determined.

PMID: 11394463

Computer terminal work and the benefit of microbreaks.

Mclean L, Tingley M, Scott RN, Rickards J., Appl Ergon. 2001 Jun; 32(3):225-37.
Source
School of Physiotherapy, Dalhousie University, Halifax, NS, Canada. linda.mclean@dal.ca Abstract

Microbreaks are scheduled rest breaks taken to prevent the onset or progression of cumulative trauma disorders in the computerized workstation environment. The authors examined the benefit of microbreaks by investigating myoelectric signal (MES) behavior, perceived discomfort, and worker productivity while individuals performed their usual keying work. Participants were ran- domly assigned to one of three experimental groups. Each participant provided data from working sessions where they took no breaks, and from working sessions where they took breaks according to their group assignment: microbreaks at their own discretion (control), microbreaks at 20 min intervals, and microbreaks at 40 min intervals. Four main muscle areas were studied: the cervical extensors, the lumbar erector spinae, the upper trapezius/supraspinatus, and the wrist and finger extensors. The authors have previously shown that when computer workers remained seated at their workstation, the muscles performing sustained postural contractions displayed a cyclic trend in the mean frequency (MNF) of the MES (McLean et al., J. Electrophysiol. Kinesiol. 10 (1) (2000) 33). The data provided evidence (p < 0.05) that all microbreak protocols were associated with a higher frequency of MNF cycling at the wrist extensors, at the neck when microbreaks were taken by the control and 40 min protocol groups, and at the back when breaks were taken by the 20 and 40 min protocol groups. No significant change in the frequency of MNF cycling was noted at the shoulder. It

[page95image16104]

was determined (p < 0.05) that microbreaks had a positive effect on reducing discomfort in all areas studied during computer terminal work, particularly when breaks were taken at 20 min intervals. Finally, microbreaks showed no evidence of a detrimental effect on worker productivity. The underlying cause of MNF cycling, and its relationship to the development of discomfort or cumulative trauma disorders remains to be determined.

PMID: 11394463

A prospective study of computer users: I. Study design and incidence of musculoskeletal symptoms and disorders.

Am J Ind Med. 2002 Apr;41(4):221-35.
Gerr F, Marcus M, Ensor C, Kleinbaum D, Cohen S, Edwards A, Gentry E, Ortiz DJ, Monteilh C. Source

Department of Environmental and Occupational Health, Rollins School of Public Health, Emory University, Atlanta, Georgia 30322, USA. fgerr@sph.emory.edu
Abstract

BACKGROUND:

A prospective study of computer users was performed to determine the occurrence of and evaluate risk factors for neck or shoulder (N/S) and hand or arm (H/A) musculoskeletal symptoms (MSS) and disorders (MSD).

METHODS:

Individuals (n = 632) newly hired into jobs requiring > or = 15 hr/week of computer use were fol- lowed for up to 3 years. At study entry, workstation dimensions and worker postures were mea- sured and medical and psychosocial risk factors were assessed. Daily diaries were used to document work practices and incident MSS. Those reporting MSS were examined for specific MSD. Incidence rates of MSS and MSD were estimated with survival analysis. Cox regression models

[page96image14424]

were used to evaluate associations between participant characteristics at entry and MSS and MSD.

RESULTS:
The annual incidence of N/S MSS was 58 cases/100 person-years and of N/S MSD was 35 cases/ 100 person-years. The most common N/S MSD was somatic pain syndrome. The annual inci- dence of H/A MSS was 39 cases/100 person-years and of H/A MSD was 21 cases/100 person- years. The most common H/A disorder was deQuervain's tendonitis. Forty-six percent of N/S and 32% of H/A MSS occurred during the first month of follow-up. Gender, age, ethnicity, and prior history of N/S pain were associated with N/S MSS and MSD. Gender, prior history of H/A pain, prior computer use, and children at home were associated with either H/A MSS or MSD. CONCLUSIONS:
H/A and N/S MSS and MSD were common among computer users. More than 50% of computer users reported MSS during the first year after starting a new job.
Copyright 2002 Wiley-Liss, Inc.
PMID: 11920966

Ergonomics. 2000 May;43(5):622-38.
A field study of supplementary rest breaks for data-entry operators. Galinsky TL, Swanson NG, Sauter SL, Hurrell JJ, Schleifer LM.
Source
National Institute for Occupational Safety and Health, Taft Laboratories, Cincinnati, Ohio 45226, USA. tlg0@cdc.gov
Abstract
This study examined the effects of supplementary rest breaks on musculoskeletal discomfort, eye- strain, mood, and performance in data- entry workers. Two rest break schedules were compared in a within- subjects design. Workers alternated between a 'conventional' and a 'supplementary' schedule in 4-week intervals. The conventional schedule contained a 15-min break during the first half of the work shift and a 15- min break during the second half of the shift. The supplementary

[page97image15240]

schedule contained the same two 15-min breaks, and a 5-min break during each hour which other- wise did not contain a break, for a total of 20 extra minutes of break time. Results are based on data from 42 workers. They indicated that discomfort in several areas of the body, and eyestrain, were significantly lower under the supplementary than under the conventional schedule. While symptoms increased from pre- to post- work periods under both schedules, the magnitude of the increases was significantly less under the supplementary schedule. In addition, increases in dis- comfort of the right forearm, wrist and hand over the course of the work week under the conventional schedule were eliminated under the supplementary schedule. These beneficial effects were obtained without reductions in data-entry performance.
PMID: 10877480

Musculoskeletal / Computer workers

The effectiveness of a work style intervention and a lifestyle physical activity intervention on the recovery from neck and upper limb symptoms in computer workers. Pain. 2007 Nov;132(1-2):142-53. Epub 2007 Sep 4.

Bernaards CM, Ariëns GA, Knol DL, Hildebrandt VH.
Source
Institute for Research in Extramural Medicine, Department of Occupational and Public Health, VU University Medical Center, Amsterdam, The Netherlands. claire.bernaards@tno.nl

Abstract
This study assessed the effectiveness of a single intervention targeting work style and a combined intervention targeting work style and physical activity on the recovery from neck and upper limb symptoms. Computer workers with frequent or long-term neck and upper limb symptoms were randomised into the work style group (WS, n=152), work style and physical activity group (WSPA, n=156), or usual care group (n=158). The WS and WSPA group attended six group meetings.

[page98image15240]

All meetings focused on behavioural change with regard to body posture, workplace adjustment, breaks and coping with high work demands (WS and WSPA group) and physical activity (WSPA group). Pain, disability at work, days with symptoms and months without symptoms were measured at baseline and after 6 (T1) and 12 months (T2). Self-reported recovery was assessed at T1/T2. Both interventions were ineffective in improving recovery. The work style intervention but not the combined intervention was effective in reducing all pain measures. These effects were present in the neck/shoulder, not in the arm/wrist/hand. For the neck/shoulder, the work style intervention group also showed an increased recovery-rate. Total physical activity increased in all study groups but no differences between groups were observed. To conclude, a group-based work style intervention focused on behavioural change was effective in improving recovery from neck/ shoulder symptoms and reducing pain on the long-term. The combined intervention was ineffective in increasing total physical activity. Therefore we cannot draw conclusions on the effect of increasing physical activity on the recovery from neck and upper limb symptoms. Comment in

•Workstyle: it's probably time we address both biomechanical and biobehavioral approaches? [Pain. 2007]
PMID: 17768009

Musculoskeletal

Ergonomics. 2000 Apr;43(4):486-93.

Lumbar erector spinae oxygenation during prolonged contractions: implications for prolonged work., McGill SM, Hughson RL, Parks K.

Source: Faculty of Applied Health Sciences, Department of Kinesiology, University of Waterloo, Canada. mcgill@healthy.uwaterloo.ca
Abstract
Owing to the recent interest in torso stabilization exercises together with many questions regard- ing the duration of prolonged isometric holds in occupational settings, the authors attempted to assess the level of back

[page99image15256]

muscle oxygenation during prolonged isometric contractions. Specifically, this study recorded relative oxygen saturation of haemoglobin/myoglobin using Near Infrared Spectroscopy (NIRS) in the L3 erector mass during prolonged isometric contractions at intensities from 2 to 30% of maximum voluntary contraction (MVC). It was hypothesized that available oxy- gen to these muscles is severely compromised even at moderate levels of activation observed in occupational work. Eight volunteers without a history of lower back pain or injury participated in this study. The exercise task involved isometric contraction of the lower erector spinae at five dif- ferent levels of each subject's maximal voluntary contraction: 2, 5, 10, 20 and 30% MVC, pre- sented in random order. Subjects were placed in a sitting position, with a curved plastic plate secured horizontally to the pelvis to minimize movement at the hip joint. During extensor exer- tions, they were restrained with a harness that was attached at chest level to a load cell. Each iso- metric contraction was performed for 30 s followed by 1 min of rest. All levels of contraction demonstrated reduction in oxygen. Given the concern for motion artefact on the NIRS signal, sham trials were conducted where the subjects went through the procedure of attaching the pull- ing cable but no active pull was performed. These trials showed no change in the NIRS signal. At this time NIRS appears to be the only non-invasive instrumentation available to indicate total available muscle oxygen during low level, prolonged work. Although the specific tissue volume sampled by NIRS cannot be positively identified, it appears that tissue oxygenation in the lumbar extensor musculature is reduced as a function of contraction intensity, even at levels as low as 2% of MVC. These data have implications for prolonged work where postures requiring isometric contractions are sometimes held for hours, and where musculoskeletal illness has been linked to prolonged contraction levels above 2%MVC--these data suggest a possible biological pathway.

PMID: 10801082

Biomechanical effects of sitting with adjustable ischial and lumbar support on occupational low back pain: evaluation of sitting load and back muscle activity. BMC Musculoskelet Disord. 2009 Feb 5;10:17.

Makhsous M, Lin F, Bankard J, Hendrix RW, Hepler M, Press J. Source
Department of Physical Therapy and Human Movement Sciences, Northwestern University, Chi- cago, IL, USA. m- makhsous2@northwestern.edu

Abstract
BACKGROUND:
Compared to standing posture, sitting decreases lumbar lordosis, increases low back muscle activ- ity, disc pressure, and pressure on the ischium, which are associated with occupational LBP. A sit- ting device that reduces spinal load and low back muscle activities may help increase sitting comfort and reduce LBP risk. The objective of this study is to investigate the biomechanical effect of sitting with a reduced ischial support and an enhanced lumbar support (Off-Loading) on load, interface pressure and muscle activities.
METHODS:

A laboratory test in low back pain (LBP) and asymptomatic subjects was designed to test the bio- mechanical effect of using the Off-Loading sitting posture. The load and interface pressure on seat and the backrest, and back muscle activities associated with usual and this Off-Loading posture were recorded and compared between the two postures.

RESULTS:
Compared with Normal (sitting upright with full support of the seat and flat backrest) posture, sit- ting in Off-Loading posture significantly shifted the center of the force and the peak pressure on the seat anteriorly towards the thighs. It also significantly decreased the contact area on the seat and increased that on the backrest. It decreased the

[page101image14648] [page101image14808]

lumbar muscle activities significantly. These effects are similar in individuals with and without LBP.
CONCLUSION:
Sitting with reduced ischial support and enhanced lumbar support resulted in reduced sitting load on the lumbar spine and reduced the lumbar muscular activity, which may potentially reduce sit- ting-related LBP.

PMID: 19193245

Association between sitting and occupational LBP. Eur Spine J. 2007 Feb;16(2):283-98. Epub 2006 May 31.
Lis AM, Black KM, Korn H, Nordin M.
Source

Occupational and Industrial Orthopaedic Center, New York, NY, USA.

al96@nyu.edu

Abstract
Low back pain (LBP) has been identified as one of the most costly disorders among the world- wide working population. Sitting has been associated with risk of developing LBP. The purpose of this literature review is to assemble and describe evidence of research on the association between sitting and the presence of LBP. The systematic literature review was restricted to those occupa- tions that require sitting for more than half of working time and where workers have physical co- exposure factors such as whole body vibration (WBV) and/or awkward postures. Twenty-five studies were carefully selected and critically reviewed, and a model was developed to describe the relationships between these factors. Sitting alone was not associated with the risk of developing LBP. However, when the co-exposure factors of WBV and awkward postures were added to the analysis, the risk of LBP increased fourfold. The occupational group that showed the strongest association with LBP was Helicopter Pilots (OR=9.0, 90% CI 4.9-16.4). For all studied occupations, the odds ratio (OR) increased when WBV and/or awkward postures were analyzed as co- exposure factors. WBV while

[page102image15296]

sitting was also independently associated with non-specific LBP and sciatica. Vibration dose, as well as vibration magnitude and duration of exposure, were associated with LBP in all occupations. Exposure duration was associated with LBP to a greater extent than vibration magnitude. However, for the presence of sciatica, this difference was not found. Awkward posture was also independently associated with the presence of LBP and/or sciatica. The risk effect of prolonged sitting increased significantly when the factors of WBV and awkward postures were combined. Sitting by itself does not increase the risk of LBP. However, sitting for more than half a workday, in combination with WBV and/or awkward postures, does increase the likelihood of having LBP and/or sciatica, and it is the combination of those risk factors, which leads to the greatest increase in LBP.

PMID: 16736200

Effects of Breaking up Prolonged Sitting on Skeletal Muscle Gene Expression. J Appl Physiol. 2012 Dec 27. [Epub ahead of print] Latouche C, Jowett JB, Carey AL, Bertovic DA, Owen N, Dunstan DW, Kingwell BA.

Source
1Baker IDI Heart and Diabetes Institute.
Abstract
Breaking up prolonged sitting has been beneficially associated with cardio-metabolic risk markers in both observational and intervention studies. We aimed to define the acute transcriptional events induced in skeletal muscle by breaks in sedentary time. Overweight/obese adults participated in a randomized three-period, three-treatment cross-over trial in an acute setting. The three 5 hour interventions were performed in the post-prandial state after a standardized test drink and included: seated position with no activity, seated with 2-minute bouts of light- or moderate- intensity treadmill walking every 20 minutes. Vastus lateralis biopsies were obtained in 8 participants after each treatment and gene expression examined using microarrays validated with real-time qPCR.

There were 75 differentially-expressed genes between the three conditions. Path- way analysis indicated the main biological functions affected were related to small molecule bio- chemistry, cellular development, growth and proliferation and carbohydrate metabolism. Interestingly, differentially expressed genes were also linked to cardiovascular disease. For example, relative to prolonged sitting, activity bouts increased expression of Nicotamide N-meth- yltransferase (NNMT), which modulates anti-inflammatory and anti-oxidative pathways and triglyceride metabolism. Activity bouts also altered expression of 10 genes involved in carbohydrate metabolism including increased expression of dynein light chain (DYNLL1), which may regulate translocation of the GLUT4 glucose transporter. In addition, breaking up sedentary time reversed the effects of chronic inactivity on expression of some specific genes. This study provides insight into the muscle regulatory systems and molecular processes underlying the physiological benefits induced by interrupting prolonged sitting.

PMID: 23271697

Obesity

Trends over 5 decades in U.S. occupation-related physical activity and their associations with obesity.

Church TS, Thomas DM, Tudor-Locke C, Katzmarzyk PT, Earnest CP, Rodarte RQ, Martin CK, Blair SN, Bouchard C., PLoS One. 2011;6(5):e19657. Epub 2011 May 25.
Source

Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, Louisiana, United States of America. tim.church@pbrc.edu

Abstract
BACKGROUND:
The true causes of the obesity epidemic are not well understood and

[page104image12960]

there are few longitudinal population-based data published examining this issue. The objective of this analysis was to exam- ine trends in occupational physical activity during the past 5 decades and explore how these trends relate to concurrent changes in body weight in the U.S. METHODOLOGY/PRINCIPAL FINDINGS:

Analysis of energy expenditure for occupations in U.S. private industry since 1960 using data from the U.S. Bureau of Labor Statistics. Mean body weight was derived from the U.S. National Health and Nutrition Examination Surveys (NHANES). In the early 1960's almost half the jobs in private industry in the U.S. required at least moderate intensity physical activity whereas now less than 20% demand this level of energy expenditure. Since 1960 the estimated mean daily energy expenditure due to work related physical activity has dropped by more than 100 calories in both women and men. Energy balance model predicted weights based on change in occupation-related daily energy expenditure since 1960 for each NHANES examination period closely matched the actual change in weight for 40-50 year old men and women. For example from 1960-62 to 2003- 06 we estimated that the occupation- related daily energy expenditure decreased by 142 calories in men. Given a baseline weight of 76.9 kg in 1960-02, we estimated that a 142 calories reduction would result in an increase in mean weight to 89.7 kg, which closely matched the mean NHANES weight of 91.8 kg in 2003-06. The results were similar for women.

CONCLUSION:
Over the last 50 years in the U.S. we estimate that daily occupation- related energy expenditure has decreased by more than 100 calories, and this reduction in energy expenditure accounts for a significant portion of the increase in mean U.S. body weights for women and men.
PMID: 21647427; PMCID:
FREE ARTICLE
“Over the last 50 years in the U.S. there has been a progressive decrease in the percent of individuals employed in goods producing and agriculture occupations whereas there has been an increase in the percent of individuals employed in service occupations. This has

resulted in a shift away from occupations that require moderate intensity physical activity to occupations that are largely composed of sitting and sedentary behavior. In the early 1960's almost half of private industry occupations in the U.S. required at least moderate intensity physical activity and now less than 20% demand this level of activity. We estimate that daily occupation-related energy expenditure has decreased by more than 100 calories in both women and men, and further, this reduction in occupational energy expenditure accounts for a large portion of the observed increase in mean U.S. weight over the last 5 decades.

“Examining secular changes in total daily physical activity is a complex endeavor. Two examples include the observation that time spent in recreational activities has increased but so has time spent watching TV. At the same time, time spent on household work has greatly decreased in women but slightly increased in men [6]. Dissecting the relative importance of each of these activities of daily living on body weight is challenging. Here we chose to focus on occupation-related energy expenditure because time spent at work represents the largest segment of waking hours for most people in the age range we studied. It is important to note that we examined the prevalence of different occupations, not absolute number of jobs in a given occupation. This is important because the workforce is not a static population and over the last 50 years the prevalence of Americans in the Labor Force has increased from approximately 40% to 50% [18]. One of the driving forces behind the increased prevalence of working Americans is the increase of women in the work force. In 1970 43% percent of women were in the labor force and by 2007 this increased to 60% of women. This fact may also explain why occupation-related energy expenditure estimated a higher mean weight during the years of 1971 to 1994 but closely matched the mean weight of women from NHANES during the period of 1999–2002”

“Our estimation of a reduction of more than 100 calories per day in occupation-related energy expenditure over the last 50 years would have been adequately compensated for by meeting the 2008 federal physical activity recommendations of 150 minutes per week of moderate intensity activity or 75 minutes per week of vigorous intensity activity [13]. While it is often noted that the prevalence of Americans who achieve this recommendation has been constant over recent decades, the fact remains that based on self-report data only 1 in 4 Americans achieve this level [19]. It is important to note that when physical activity is assessed with accelerometers the num- ber of Americans that achieve the physical activity recommendations falls to 1 in 20” PMC3102055 Free PMC Article

The association between television viewing and overweight among Australian adults participating in varying levels of leisure-time physical activity.

Salmon J, Bauman A, Crawford D, Timperio A, Owen N.nt J Obes Relat Metab Disord. 2000 May;24(5):600-6.
Source
School of Health Sciences, Deakin University, 221 Burwood Hwy, Burwood, Victoria 3125, Aus- tralia.

Abstract
OBJECTIVES:
To investigate the effect of physical activity on the association between television viewing and overweight (body mass index (BMI) > or =25 kg/ m2).
DESIGN:
Cross-sectional study administered by interview to adults randomly selected from the electronic white pages.
SUBJECTS:
3392 adults (64% response rate) from a representative population sample in the State of New South Wales, Australia.
MEASUREMENTS:

Self-reported height and weight, two-week leisure-time physical activity recall, one-week average television viewing recall.
RESULTS:
BMI and physical activity patterns were both associated with hours of television watched. Com- pared to those participants who reported watching less than one hour of television per day, those watching 1 to 2.5 hours were 93% more likely to be overweight (BMI>/=25 kg/m2), those watch- ing 2.5 to 4 hours were 183% more likely to be overweight, those watching more than 4 hours per day were four times more likely to be overweight. Physical activity was not directly associated with being overweight, but an interaction between activity and television watching was present. Respondents in the low, moderate and high physical activity categories who reported watching more than 4 hours of television per day were twice as likely to be overweight compared to those who watched less than one hour of television per day, irrespective of physical activity participa- tion.

CONCLUSIONS:
With approximately half the Australian adult population overweight or obese, these findings indi- cate that public health strategies to reduce overweight and prevent weight gain may need to focus on reducing sedentary behaviours such as television viewing in addition to increasing physical activity.
PMID: 10849582

Role of nonexercise activity thermogenesis in resistance to fat gain in humans.

Science 1999;283:212–214 Abstract/FREE Full Text Levine JA, Eberhardt NL, Jensen MD.

Humans show considerable interindividual variation in susceptibility to weight gain in response to overeating. The physiological basis of this variation was investigated by measuring changes in energy storage and expenditure in 16 nonobese volunteers who were fed 1000 kilocalories per day in excess of weight-maintenance requirements for 8 weeks.

Two-thirds of the increases in total daily energy expenditure was due to increased nonexercise activity thermogenesis (NEAT), which is associated with fidgeting, maintenance of posture, and other physical activities of daily life. Changes in NEAT accounted for the 10-fold differences in fat storage that occurred and directly predicted resistance to fat gain with overfeeding (correlation coefficient = 0.77, probability < 0.001). These results suggest that as humans overeat, activation of NEAT dissipates excess energy to preserve leanness and that failure to activate NEAT may result in ready fat gain. http:// www.ncbi.nlm.nih.gov/pubmed/9880251

Interindividual variation in posture allocation: possible role in human obesity.

Levine JA, Eberhardt NL, Jensen MD.
Source
Department of Medicine, Endocrine Research Unit, Mayo Clinic and Mayo Foundation, 200 First Street Southwest, Rochester, MN 55905, USA.
Abstract
Humans show considerable interindividual variation in susceptibility to weight gain in response to overeating. The physiological basis of this variation was investigated by measuring changes in energy storage and expenditure in 16 nonobese volunteers who were fed 1000 kilocalories per day in excess of weight-maintenance requirements for 8 weeks. Two-thirds of the increases in total daily energy expenditure was due to increased nonexercise activity thermogenesis (NEAT), which is associated with fidgeting, maintenance of posture, and other physical activities of daily life. Changes in NEAT accounted for the 10-fold differences in fat storage that occurred and directly predicted resistance to fat gain with overfeeding (correlation coefficient = 0.77, probability < 0.001). These results suggest that as humans overeat, activation of NEAT dissipates excess energy to preserve leanness and that failure to activate NEAT may result in ready fat gain.

[page109image15048] [page109image15208]

Physical activity for obese individuals: a systematic review of effects on chronic disease risk factors.

Katzmarzyk PT, Lear SA., Obes Rev. 2011 Sep 26. doi: 10.1111/j. 1467-789X.2011.00933.x. Obes Rev. 2011 Sep 26. doi: 10.1111/j. 1467-789X.2011.00933.x. [Epub ahead of print]
Source

Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, LA, USA Faculty of Health Sciences, Simon Fraser University, Vancouver, BC, Canada.

Abstract
The purpose of this review was to determine the effectiveness of physical activity in improving chronic disease risk factors in obese individuals. A systematic review was conducted to identify randomized physical activity intervention studies reporting changes in risk factors among obese individuals published prior to March 2010. Studies included in the review were randomized trials of at least 10 weeks in duration, with a sample mean body mass index ≥30?kg/m(2) at baseline, and reporting a relevant risk factor (blood pressure, blood lipids, glucose/insulin or C-reactive protein). Forty-four studies met the inclusion criteria for this review. Overall, physical activity had no more than a modest effect on chronic disease risk factors in obese individuals. There was great heterogeneity in responses of risk factors across studies. In many studies it was difficult to deter- mine the effect of physical activity, independent of changes in body mass consequent to the inter- vention. Obese individuals should be encouraged to undertake physical activity following general recommendations for weight loss and health. The degree to which physical activity is effective at lowering risk factor levels among high-risk obese individuals is not known.
© 2011 The Authors. obesity reviews © 2011 International Association for the Study of Obesity. PMID: 21951422

Associations of leisure-time internet and computer use with

overweight and obesity, physical activity and sedentary behaviors: cross-sectional study.
Vandelanotte C, Sugiyama T, Gardiner P, Owen N. J Med Internet Res. 2009 Jul 27;11(3):e28. doi: 10.2196/jmir.1084.

Source
Institute for Health and Social Sciences Research, Central Queensland University, Rockhampton, Australia. c.vandelanotte@cqu.edu.au Abstract
BACKGROUND:

Internet and computer use are increasingly common leisure-time sedentary behaviors, which have the potential to impact negatively on health outcomes. However, little is known about the extent to which adults' Internet and computer use is associated with weight status and time spent in leisure- time physical activity.

OBJECTIVE:
The objective is to examine associations of leisure-time Internet and computer use with over- weight and obesity, leisure-time physical activity, and other sedentary behaviors.
METHODS:
Participants (2650 adults living in Adelaide, Australia) completed a mail-back questionnaire including items on their height and weight, past seven day recall of leisure-time physical activity, Internet and computer use, and other leisure-time sedentary behaviors. Leisure-time Internet and computer use was categorized into no use, low use (less than three hours per week), or high use (three hours or more per week). RESULTS:
Participants with low leisure-time Internet and computer use had the highest levels of educational attainment and employment, and engaged in less other sedentary behaviors when compared to participants with no or high Internet and computer use. Multinomial logistic regression, adjusted for gender, age, employment, education, other sedentary behaviors and physical activity, deter- mined that participants with a

[page111image13952]

high leisure-time Internet and computer use were 1.46 (95% CI = 1.10 - 1.93) times more likely to be overweight (BMI> or =25 and < 30 kg/ m(2)) and 2.52 times more likely (95% CI = 1.82 - 3.52) to be obese (BMI> or =30 kg/m(2)), compared to those who reported no Internet and computer use in their leisure-time. Adults with high leisure-time Internet and computer use were more likely to be overweight or obese even if they were highly active in their leisure time (OR = 1.86; 95% CI = 1.21 - 2.88), as compared to partic- ipants who did not use the Internet or computer. Leisure-time physical activity levels were largely independent of Internet and computer use.

CONCLUSION:
These findings suggest that, apart from nutritional and physical activity interventions, it may also be necessary to decrease time spent in sedentary behaviors, such as leisure-time Internet and com- puter use, in order to reduce the prevalence of overweight and obesity. Future Internet interven- tions to reduce weight or increase physical activity may need to differentiate between participants with different levels of Internet use in order to increase their effectiveness. Longitudinal studies are required to examine further the potential causal relationships between the development of overweight and specific sedentary behaviors such as Internet and computer use.
PMID: 19666455

Television Viewing Time is Associated with Overweight/Obesity Among Older Adults, Inde- pendent of Meeting Physical Activity and Health Guidelines.

J Epidemiol. 2011 Dec 10. [Epub ahead of print]

Inoue S, Sugiyama T, Takamiya T, Oka K, Owen N, Shimomitsu T. Source
Department of Preventive Medicine and Public Health, Tokyo Medical University.

Abstract Background:

Previous studies have shown associations of sedentary behavior with cardiovascular risk, indepen- dent of moderate-to-vigorous physical activity (MVPA). However, few studies have focused on older adults. This study examined the joint associations of television (TV) viewing time and MVPA with overweight/obesity among Japanese older adults. Methods:

A population-based, cross-sectional mail survey was used to collect self- reported height, weight, time spent in TV viewing, and MVPA from 1806 older adults (age: 65-74 years, men: 51.1%). Participants were classified into 4 categories according to TV viewing time (dichotomized into high and low around the median) and MVPA level (dichotomized into sufficient and insufficient by the physical activity guideline level of ≥150 minutes/week). Odds ratios (ORs) for overweight/ obesity (body mass index ≥25 kg/m(2)) were calculated according to the 4 TV/MVPA categories, adjusting for potential confounders.

Results:
Of all participants, 20.1% were overweight/obese. The median TV viewing time (25th, 75th per- centile) was 840 (420, 1400) minutes/ week. As compared with the reference category (high TV/ insufficient MVPA), the adjusted ORs (95% CI) of overweight/obesity were 0.93 (0.65, 1.34) for high TV/sufficient MVPA, 0.58 (0.37, 0.90) for low TV/ insufficient MVPA, and 0.67 (0.47, 0.97) for low TV/sufficient MVPA.Conclusions: In this sample of older adults, spending less time watching TV, a predominant sedentary behavior, was associated with lower risk of being over- weight or obese, independent of meeting physical activity guidelines. Further studies using pro- spective and/or intervention designs are warranted to confirm the presently observed effects of sedentary behavior, independent of physical activity, on the health of older adults.
PMID: 22156288

Television Viewing Time is Associated with Overweight/Obesity Among Older Adults, Inde- pendent of Meeting Physical Activity and Health Guidelines.

J Epidemiol. 2011 Dec 10. [Epub ahead of print]

Inoue S, Sugiyama T, Takamiya T, Oka K, Owen N, Shimomitsu T. Source
Department of Preventive Medicine and Public Health, Tokyo Medical University.

Abstract
Background:
Previous studies have shown associations of sedentary behavior with cardiovascular risk, indepen- dent of moderate-to-vigorous physical activity (MVPA). However, few studies have focused on older adults. This study examined the joint associations of television (TV) viewing time and MVPA with overweight/obesity among Japanese older adults. Methods:
A population-based, cross-sectional mail survey was used to collect self- reported height, weight, time spent in TV viewing, and MVPA from 1806 older adults (age: 65-74 years, men: 51.1%). Participants were classified into 4 categories according to TV viewing time (dichotomized into high and low around the median) and MVPA level (dichotomized into sufficient and insufficient by the physical activity guideline level of ≥150 minutes/week). Odds ratios (ORs) for overweight/ obesity (body mass index ≥25 kg/m(2)) were calculated according to the 4 TV/MVPA categories, adjusting for potential confounders.
Results:
Of all participants, 20.1% were overweight/obese. The median TV viewing time (25th, 75th per- centile) was 840 (420, 1400) minutes/ week. As compared with the reference category (high TV/ insufficient MVPA), the adjusted ORs (95% CI) of overweight/obesity were 0.93 (0.65, 1.34) for high TV/sufficient MVPA, 0.58 (0.37, 0.90) for low TV/ insufficient MVPA, and 0.67 (0.47, 0.97) for low TV/sufficient MVPA.Conclusions: In this sample of older adults, spending less time watching TV, a predominant sedentary behavior, was associated with lower risk of being over- weight or obese, independent of meeting physical activity guidelines. Further studies using pro- spective and/or

intervention designs are warranted to confirm the presently observed effects of sedentary behavior, independent of physical activity, on the health of older adults.
PMID: 22156288

Associations among physical activity, television watching, and obesity in adult Pima Indians

Fitzgerald SJ, Kriska AM, Pereira MA, de Courten MP., Med Sci Sports Exerc. 1997 Jul;29(7):910-5.
Source
Department of Epidemiology, Graduate School of Public Health, University of Pittsburgh, PA 15261, USA. EPIDSJ+@PITT.EDU

Abstract
It has been suggested that television watching and physical activity are related to obesity. This association, however, has been investigated mainly in children. This study provided the opportunity to examine the relationship between television watching, physical activity, and body mass index in adult Pima Indians, a population with a high prevalence of obesity. Hours per day of tele- vision watched, past-year physical levels (MET-h/wk; leisure and occupational combined) and BMI (kg.m-2) were measured in 2452 men and women subjects 21-59 yr old. In adults between the ages of 21 and 39 yr, TV and physical activity levels were negatively correlated (r = -0.11 for men and -0.10 for women). Weaker associations were found between TV and BMI (r = 0.08 for men and 0.04 for women). There were no significant relationships among these variables in older adults (49-59 yr), possibly because of low reported levels of physical activity and TV. Multiple linear regression analysis revealed that physical activity and television watching in men and activ- ity in women were significantly related to BMI. These data suggest that increasing activity levels and decreasing the time spent in sedentary behavior such as watching television should both be considered as potential intervention strategies in obesity prevention programs.

[page115image15328]

PMID: 9243490

Women and Men

Dariush Mozaffarian, M.D., Dr.P.H., Tao Hao, M.P.H., Eric B. Rimm, Sc.D., Walter C. Willett, M.D., Dr.P.H., and Frank B. Hu, M.D., Ph.D. N Engl J Med 2011; 364:2392-2404June 23, 2011
BACKGROUND

Specific dietary and other lifestyle behaviors may affect the success of the straightforward-sound- ing strategy “eat less and exercise more” for preventing long-term weight gain.

METHODS
We performed prospective investigations involving three separate cohorts that included 120,877 U.S. women and men who were free of chronic diseases and not obese at baseline, with follow-up periods from 1986 to 2006, 1991 to 2003, and 1986 to 2006. The relationships between changes in lifestyle factors and weight change were evaluated at 4-year intervals, with multivariable adjust- ments made for age, baseline body-mass index for each period, and all lifestyle factors simulta- neously. Cohort-specific and sex-specific results were similar and were pooled with the use of an inverse-variance–weighted meta- analysis.
Full Text of Methods...

RESULTS
Within each 4-year period, participants gained an average of 3.35 lb (5th to 95th percentile, ?4.1 to 12.4). On the basis of increased daily servings of individual dietary components, 4-year weight change was most strongly associated with the intake of potato chips (1.69 lb), potatoes (1.28 lb), sugar-sweetened beverages (1.00 lb), unprocessed red meats (0.95 lb), and processed meats (0.93 lb) and was inversely associated with the intake of vegetables (?0.22 lb), whole grains (?0.37 lb), fruits (? 0.49 lb), nuts (?0.57 lb), and yogurt (?0.82 lb) (P≤0.005 for each

comparison). Aggregate dietary changes were associated with substantial differences in weight change (3.93 lb across quintiles of dietary change).

Other lifestyle factors were also independently associated with weight change (P<0.001), includ- ing physical activity (?1.76 lb across quintiles); alcohol use (0.41 lb per drink per day), smoking (new quitters, 5.17 lb; former smokers, 0.14 lb), sleep (more weight gain with <6 or >8 hours of sleep), and television watching (0.31 lb per hour per day).

Full Text of Results... CONCLUSIONS

Specific dietary and lifestyle factors are independently associated with long-term weight gain, with a substantial aggregate effect and implications for strategies to prevent obesity. (Funded by the National Institutes of Health and others. http://www.nejm.org/doi/full/10.1056/ NEJMoa1014296

The association between television viewing and overweight among Australian adults participating in varying levels of leisure-time physical activity.

Salmon J, Bauman A, Crawford D, Timperio A, Owen N.nt J Obes Relat Metab Disord. 2000 May;24(5):600-6.
Source
School of Health Sciences, Deakin University, 221 Burwood Hwy, Burwood, Victoria 3125, Australia.

Abstract
OBJECTIVES:
To investigate the effect of physical activity on the association between television viewing and overweight (body mass index (BMI) > or =25 kg/ m2).
DESIGN:

[page117image12080] [page117image12240]

Cross-sectional study administered by interview to adults randomly selected from the electronic white pages.
SUBJECTS:
3392 adults (64% response rate) from a representative population sample in the State of New South Wales, Australia.

MEASUREMENTS:
Self-reported height and weight, two-week leisure-time physical activity recall, one-week average television viewing recall.
RESULTS:
BMI and physical activity patterns were both associated with hours of television watched. Com- pared to those participants who reported watching less than one hour of television per day, those watching 1 to 2.5 hours were 93% more likely to be overweight (BMI>/=25 kg/m2), those watch- ing 2.5 to 4 hours were 183% more likely to be overweight, those watching more than 4 hours per day were four times more likely to be overweight. Physical activity was not directly associated with being overweight, but an interaction between activity and television watching was present. Respondents in the low, moderate and high physical activity categories who reported watching more than 4 hours of television per day were twice as likely to be overweight compared to those who watched less than one hour of television per day, irrespective of physical activity participation.
CONCLUSIONS:
With approximately half the Australian adult population overweight or obese, these findings indicate that public health strategies to reduce overweight and prevent weight gain may need to focus on reducing sedentary behaviours such as television viewing in addition to increasing physical activity.
PMID: 10849582

Nonexercise activity thermogenesis--liberating the life-force.

J Intern Med. 2007 Sep;262(3):273-87. Levine JA.

Source
Endocrine Research Unit, Mayo Clinic, Rochester, MN 5590, USA. levine.james@mayo.edu Abstract

Obesity occurs when energy intake exceeds energy expenditure over a protracted period of time. The energy expenditure associated with everyday activity is called NEAT (Nonexercise activity thermogenesis). NEAT varies between two people of similar size by 2000 kcal day(-1) because of people's different occupations and leisure-time activities. Data support the central hypothesis that NEAT is pivotal in the regulation of human energy expenditure and body weight regulation and that NEAT is important for understanding the cause and effective treatment for obesity.

PMID: 17697152

Activity level and risk of overweight in male health professionals.

Am J Public Health. 1996 Jan;86(1):25-30.
Ching PL, Willett WC, Rimm EB, Colditz GA, Gortmaker SL, Stampfer MJ.
Department of Health and Social Behavior, Harvard School of Public Health, Boston, Mass., Abstract
OBJECTIVES:
This study undertook to examine relationships between nonsedentary activity level, time spent watching television (TV)/videocassette recorder (VCR), and risk of overweight among men. METHODS:
Men participating in the Health Professionals Follow-Up Study were mailed surveys. Cross-sec- tional analyses examined the prevalence and odds of being overweight, prospective analyses determined cumulative incidence rates and relative risks of becoming overweight over 2 years of follow-up.
RESULTS:

[page119image12392]

Cross-sectionally, odds of being overweight were 50% (95% confidence interval [CI] = 45%; 55%) lower for men in the highest quintile of nonsedentary activity level when compared with men in the lowest quintile. Among men watching 41 or more hours of TV/VCR per week, the odds of being overweight were 4.06 (95% CI = 2.67, 6.17) times greater than those for men watching no more than 1 hour per week. Prospectively, higher levels is of nonsedentary activity and lower levels of TV/VCR viewing were independently associated with lower relative risks for becoming overweight between survey years.

CONCLUSIONS:
Both a lack of nonsedentary activity and time spent watching TV/VCR contribute to the development of overweight in men. Sedentary and nonsedentary activities represent separate domains, each with independent risks for overweight.
PMID: 8561237 [PubMed - indexed for MEDLINE] PMCID: PMC1380355

Are computer and cell phone use associated with body mass index and overweight? A population study among twin adolescents

BMC Public Health. 2007; 7: 24.
Published online 2007 February 26. doi: 10.1186/1471-2458-7-24 PMCID: PMC1820777
Copyright © 2007 Lajunen et al; licensee BioMed Central Ltd. Hanna-Reetta Lajunen,1 Anna Keski-Rahkonen,#1,2,3 Lea Pulkkinen,#4 Richard J Rose,#1,5 Aila Rissanen,#2 and Jaakko Kaprio#1,6
1Dept of Public Health, University of Helsinki, P.O. Box 41, 00014, Helsinki, Finland
2Obesity Research Unit, Dept of Psychiatry, Helsinki University Central Hospital, Helsinki, Fin- land
3Dept of Epidemiology, Mailman School of Public Health, Columbia University, New York, USA 4Dept of Psychology, University of Jyväskylä, Jyväskylä, Finland
5Dept of Psychological & Brain Sciences, Indiana University,

Bloomington, IN, USA
6Dept of Mental Health and Alcohol Research, National Public Health Institute, Helsinki, Finland Corresponding author.
#Contributed equally.
Hanna-Reetta Lajunen: hanna-reetta.lajunen@helsinki.fi; Anna Keski- Rahkonen: anna.keski-rah- konen@helsinki.fi; Lea Pulkkinen: lea.pulkkinen@psyka.jyu.fi; Richard J Rose: rose@indi- ana.edu; Aila Rissanen: aila.rissanen@medi.inet.fi; Jaakko Kaprio: jaakko.kaprio@helsinki.fi Received June 16, 2006; Accepted February 26, 2007.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/ licenses/by/2.0), which permits unrestricted use, distribu- tion, and reproduction in any medium, provided the original work is properly cited.

This article has been cited by other articles in PMC. • Other Sections? Abstract
Background

Overweight in children and adolescents has reached dimensions of a global epidemic during recent years. Simultaneously, information and communication technology use has rapidly increased.
Methods

A population-based sample of Finnish twins born in 1983–1987 (N = 4098) was assessed by self- report questionnaires at 17 y during 2000– 2005. The association of overweight (defined by Cole's BMI-for-age cut- offs) with computer and cell phone use and ownership was analyzed by logistic regression and their association with BMI by linear regression models. The effect of twinship was taken into account by correcting for clustered sampling of families. All models were adjusted for gender, physical exercise, and parents' education and occupational class.

Results

[page121image13048] [page121image13208] [page121image13368] [page121image13528] [page121image13688] [page121image13848] [page121image14008]

The proportion of adolescents who did not have a computer at home decreased from 18% to 8% from 2000 to 2005. Compared to them, having a home computer (without an Internet connection) was associated with a higher risk of overweight (odds ratio 2.3, 95% CI 1.4 to 3.8) and BMI (beta coefficient 0.57, 95% CI 0.15 to 0.98). However, having a computer with an Internet connection was not associated with weight status. Belonging to the highest quintile (OR 1.8 95% CI 1.2 to 2.8) and second-highest quintile (OR 1.6 95% CI 1.1 to 2.4) of weekly computer use was positively associated with overweight. The proportion of adolescents without a personal cell phone decreased from 12% to 1% across 2000 to 2005. There was a positive linear trend of increasing monthly phone bill with BMI (beta 0.18, 95% CI 0.06 to 0.30), but the association of a cell phone bill with overweight was very weak.

Conclusion
Time spent using a home computer was associated with an increased risk of overweight. Cell phone use correlated weakly with BMI. Increasing use of information and communication technology may be related to the obesity epidemic among adolescents. http://www.ncbi.nlm.nih.gov/pmc/ articles/PMC1820777/

Associations of leisure-time internet and computer use with overweight and obesity, physical activity and sedentary behaviors: cross-sectional study. J Med Internet Res. 2009 Jul 27;11(3):e28. Vandelanotte C, Sugiyama T, Gardiner P, Owen N.
Source
Institute for Health and Social Sciences Research, Central Queensland University, Rockhampton, Australia. c.vandelanotte@cqu.edu.au Abstract
BACKGROUND:
Internet and computer use are increasingly common leisure-time sedentary behaviors, which have the potential to impact negatively on health outcomes. However, little is known about the extent to which

[page122image15192] [page122image15352] [page122image15512]

adults' Internet and computer use is associated with weight status and time spent in leisure- time physical activity.
OBJECTIVE:
The objective is to examine associations of leisure-time Internet and computer use with over- weight and obesity, leisure-time physical activity, and other sedentary behaviors.

METHODS:
Participants (2650 adults living in Adelaide, Australia) completed a mail-back questionnaire including items on their height and weight, past seven day recall of leisure-time physical activity, Internet and computer use, and other leisure-time sedentary behaviors. Leisure-time Internet and computer use was categorized into no use, low use (less than three hours per week), or high use (three hours or more per week). RESULTS:
Participants with low leisure-time Internet and computer use had the highest levels of educational attainment and employment, and engaged in less other sedentary behaviors when compared to participants with no or high Internet and computer use. Multinomial logistic regression, adjusted for gender, age, employment, education, other sedentary behaviors and physical activity, deter- mined that participants with a high leisure-time Internet and computer use were 1.46 (95% CI = 1.10 - 1.93) times more likely to be overweight (BMI> or =25 and < 30 kg/ m(2)) and 2.52 times more likely (95% CI = 1.82 - 3.52) to be obese (BMI> or =30 kg/m(2)), compared

to those who reported no Internet and computer use in their leisure-time. Adults with high leisure-time Internet and computer use were more likely to be overweight or obese even if they were highly active in their leisure time (OR = 1.86; 95% CI = 1.21 - 2.88), as compared to participants who did not use the Internet or computer. Leisure-time physical activity levels were largely independent of Internet and computer use.

CONCLUSION:
These findings suggest that, apart from nutritional and physical activity interventions, it may also be necessary to decrease time spent in sedentary behaviors, such as leisure-time Internet and com- puter use, in order to reduce the prevalence of overweight and obesity. Future Internet interven- tions to reduce weight or increase physical activity may need to differentiate between participants with different levels of Internet use in order to increase their effectiveness. Longitudinal studies are required to examine further the potential causal relationships between the development of overweight and specific sedentary behaviors such as Internet and computer use.
PMID: 19666455

Sitting time and socio-economic differences in overweight and obesity. Int J Obes (Lond). 2007 Jan;31(1):169-76. Epub 2006 Apr 25. Proper KI, Cerin E, Brown WJ, Owen N.
Source
Cancer Prevention Research Centre, School of Population Health, The University of Queensland, Herston, Brisbane, Australia. ki.proper@vumc.nl
Abstract
OBJECTIVES:
To examine (1) the inter-relationships between socio-economic status (SES), physical activity, three different domains of sitting time (weekday, weekend day and leisure-time sitting), and being overweight or obese (body mass index>/=25 kg/m(2)); and (2) the potential mediation effects of sitting time in the relationship between socio- economic factors and being overweight or obese in working Australian adults.
DESIGN:
Observational epidemiological study.
SUBJECTS:
One thousand forty eight working adults. Using a multistage sampling

[page124image12968]

design on neighbourhood SES, participants were from high and low SES neighbourhoods of an Australian capital city. MEASUREMENTS: Neighbourhood SES was assessed using census data; individual SES was based on self-reported educational attainment and household income. There were three sitting time variables: sitting time on weekdays, weekend days and in leisure time. Overweight and obesity were determined using self-reported body weight and height. RESULTS:

Gender, age, neighbourhood SES, education, working hours and physical activity were indepen- dently associated with weekday, weekend day and leisure-related sitting time. With the exception of education and working hours, these variables were also independently associated with being overweight or obese. Leisure-time sitting was found to be a mediator in the relationships between gender, education and being overweight or obese.

CONCLUSION:

Strategies to promote less sitting in leisure time are required to combat overweight and obesity in Australian adults, especially among those from low SES neighbourhoods, and among those with high levels of education and income who work long hours.

PMID: 16652126

Sitting time and work patterns as indicators of overweight and obesity in Australian adults. Brown WJ, Miller YD, Miller R. Source
School of Human Movement Studies, University of Queensland, Australia. wbrown@hms.uq.edu.au

Abstract
BACKGROUND:
Increasing levels of physical inactivity and sedentariness are contributing to the current over- weight and obesity epidemic. In this paper, the findings of two recent studies are used to explore the relationships between sitting time (in transport, work and leisure),

[page125image14408]

physical activity and body mass index (BMI) in two contrasting samples of adult Australians.
METHODS:
Data on sitting time, physical activity, BMI and a number of demographic characteristics were compared for participants in two studies-529 women who were participants in a preschool health promotion project ('mothers'), and 185 men and women who were involved in a workplace pedometer study ('workers'). Relationships between age, number of children, physical activity, sit- ting time, BMI, gender and work patterns were explored. Logistic regression was used to predict the likelihood of being overweight or obese, among participants with different physical activity, sitting time and work patterns. RESULTS:

The total reported time spent sitting per day (across all domains) was almost 6 h less among the mothers than the workers (P<0.001), and compared with the mothers, a significantly greater pro- portion of the workers was classified as overweight or obese (BMI > or =25 kg/m(2)). Univariate analysis found that, compared with men in full-time work, women who worked full-time (OR=0.42, CI: 0.24-0.74), part-time (OR=0.35, CI: 0.20-0.59) or in full-time home duties (OR=0.51, CI: 0.29-0.88) were about half as likely to be overweight or obese. Participants who reported high daily levels of sitting (> or =7.4 h) were also significantly more likely than those who reported 'low' levels (<4.7 h/day) to be overweight or obese (OR=1.68, CI: 1.16-2.42). Multi- variate analysis (including physical activity, work patterns and sitting time) confirmed that full- time and part-time working women (but not 'home duties' women) were less likely to report BMI > or =25 kg/m(2) than full-time working men (full-time: OR=0.44, CI: 0.25-0.78; part- time: OR=0.45, CI: 0.24-0.86), but the OR for BMI > or =25 among those in the high sitting category was attenuated (OR=1.61, CI 0.96-2.71).

CONCLUSIONS:
The findings suggest a need for inclusion of measures of both activity and inactivity in future studies, so that the complex relationships

between these behavioural determinants of BMI can be clarified. PMID: 14574344

Older adults

Correlates of prolonged television viewing time in older Japanese men and women.

BMC Public Health. 2013 Mar 9;13:213. doi: 10.1186/1471-2458-13-213.
Kikuchi H, Inoue S, Sugiyama T, Owen N, Oka K, Shimomitsu T. Source
Department of Preventive Medicine and Public Health, Tokyo Medical University, Tokyo, Japan. kikuchih@tokyo-med.ac.jp

Abstract
BACKGROUND:
In addition to insufficient moderate-to-vigorous physical activity (MVPA), prolonged sitting time is also a health risk for older adults. An understanding of population subgroups who have pro- longed television viewing (TV) time, a predominant sedentary behavior, can aid in the develop- ment of relevant health promotion initiatives; however, few such studies have focused on older adults, the most sedentary segment of the population as a whole. The aim of this study is to exam- ine the socio-demographic attributes associated with TV time among community-dwelling Japa- nese older men and women.
METHODS:
A population-based, cross-sectional mail survey was used to collect data on TV time, MVPA, and socio-demographic characteristics. The survey was conducted from February through March 2010. Participants were 2700 community-dwelling older adults (aged 65-74 years, 50% men) who were randomly selected from the registry of residential addresses of three cities in Japan. Data from 1665 participants (mean age: 69.5 years, 52% men) who completed all variables for the

[page127image13216]

present study were analyzed. Multivariate logistic regression analyses were used to calculate the odds ratios (ORs) of prolonged TV time (>2 hours/day) for each socio-demographic attribute, stratified by gender. RESULTS:

Of the 1665 participants, 810 (48.6%) watched TV for more than 2 hours/day. The median television viewing time (25th, 75th percentile) was 2.00 (1.07, 3.50) hours/day. Prolonged TV time was associated with not in full-time employment, lower educational attainment, weight status, living in regional areas and low MVPA for the whole sample. For men, prolonged TV time was associ- ated with lower educational attainment; (OR?=?1.53, 95% CI: 1.12-2.07), underweight (OR?=?1.63, 95% CI: 1.02-2.60), overweight (OR?=?1.57, 95% CI: 1.11-2.21), and low MVPA (OR?=?1.43, 95% CI: 1.02-2.02). For women, living in regional areas (OR?=?2.02, 95% CI: 1.33- 3.08), living alone (OR?=? 1.61, 95% CI: 1.03-2.49), not driving (OR?=?1.79, 95% CI 1.21-2.65), overweight (OR?=?1.50, 95% CI: 1.00-2.24), and low MVPA (OR?=? 1.51. 95% CI: 1.05-2.17) were associated with prolonged TV time.

CONCLUSIONS:
These findings identify particular socio-demographic and behavioral characteristics related to TV time among Japanese older adults. It should be noted that correlates of prolonged TV time differed by gender. Women in living situations with limited transportation options tended to spend prolonged time watching TV. Health promotion initiatives for older adults, particularly for older women, may be more effective if they take these attributes into account.
PMID: 23496962

Sedentary Behavior, Physical Activity, and Markers of Health in Older Adults.

Med Sci Sports Exerc. 2013 Mar 5. [Epub ahead of print] Gennuso KP, Gangnon RE, Matthews CE, Thraen-Borowski KM, Colbert LH.

Source
1Department of Kinesiology, University of Wisconsin-Madison, Madison, WI 2Department of Population Health Sciences, University of Wisconsin-Madison, Madison, WI 3Department of Biostatistics and Medical Informatics, University of Wisconsin-Madison, WI 4Nutritional Epide- miology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, Bethesda, MD.
Abstract
INTRODUCTION:
To examine the association between sedentary behavior (SB), cardiometabolic risk factors, and self-reported physical function by level of moderate-vigorous physical activity (MVPA). METHODS: Cross-sectional analysis was completed on 1, 914 older adults aged ≥65 years from the 2003-2006 U.S. National Health and Nutrition Examination Survey (NHANES). MVPA and SB were derived from Actigraph accelerometers worn for one week. MVPA was categorized as sufficient to meet the current U.S. guidelines (≥150 minutes/week) or not; SB was split into quartiles. Various biom- arkers were examined in laboratory analyses and physical exams, and the number of functional limitations was self-reported. Statistical interaction between SB and MVPA on the biomarker associations was the primary analysis, followed by an examination of their independent associa- tions with relevant covariate adjustment.
RESULTS:
Average SB was 9.4±2.3 hours/day (mean ± SD) and approximately 35% were classified as suffi- ciently active. Overall, no significant meaningful statistical interactions were found between SB and MVPA for any of the outcomes; however, strong independent positive associations were found between SB and weight (p<0.01), BMI (p<0.01), waist circumference (p<0.01), C-reactive protein (CRP) (p<0.01), plasma glucose (p=0.04), and number of functional limitations (p<0.01) after adjustment for MVPA. Similarly, MVPA was negatively associated with weight (p=0.01), BMI (p<0.01), waist circumference (p<0.01), diastolic blood pressure (p=0.04), CRP (p<0.01), and number

of functional limitations (p<0.01) after adjustment for SB. CONCLUSION:
The results suggest that sufficient MVPA did not ameliorate the negative associations between SB and cardiometabolic risk factors or functional limitations in the current sample and that there was

independence on a multiplicative scale in their associations with the outcomes examined. Thus, older adults may benefit from the joint prescription to accumulate adequate MVPA and avoid pro- longed sitting. PMID: 23475142

Semen quality

Physical activity and television watching in relation to semen quality in young men.

Gaskins AJ, Mendiola J, Afeiche M, Jørgensen N, Swan SH, Chavarro JE., Br J Sports Med. 2013 Feb 4. [Epub ahead of print]
Department of Nutrition, Harvard School of Public Health, Boston, Massachusetts, USA. Abstract

BACKGROUND:
Semen quality appears to have declined over the past decades but reasons for this decline are unresolved. The concurrent increase in sedentary behaviour may be a contributing factor. The objective of this study was to evaluate the relationship of physical activity and television (TV) watching with sperm parameters in a population of young, healthy men.
METHODS:
Men aged 18-22 years (n=189) from the Rochester Young Men's Study (2009-2010) participated in this analysis. Physical activity (h/week of moderate and vigorous exercise) and TV watching (h/week of TV, video or DVD watching) over the past 3 months were assessed via questionnaire. Semen quality was assessed by sperm concentration, motility, morphology and total sperm count. RESULTS:

Sperm concentration and total sperm count were directly related to physical activity after multi- variable adjustment (p-trend=0.01 and 0.04); men in the highest quartile of moderate-to-vigorous activity (≥15 h/week) had 73% (95% CI 15% to 160%) higher sperm concentration than men in the lowest quartile (<5 h/week). TV watching was inversely associated with sperm concentration and total sperm count in multivariable analyses (p-trend=0.05 and 0.06); men in the highest quar- tile of TV watching (>20 h/week) had 44% (95% CI 15 to 63%) lower sperm concentration than men in the lowest quartile (0 h/week). These measures of physical and leisure time activities were not significantly associated with sperm motility or morphology.

CONCLUSIONS:
In this population of healthy men, higher moderate-to-vigorous activity and less TV watching were significantly associated with higher total sperm count and sperm concentration.
PMID: 23380634

Sitting

The descriptive epidemiology of sitting. A 20-country comparison using the International Physical Activity Questionnaire (IPAQ).

Bauman A, Ainsworth BE, Sallis JF, Hagströmer M, Craig CL, Bull FC, Pratt M, Venugopal K, Chau J, Sjöström M; IPS Group.Am J Prev Med. 2011 Aug;41(2):228-35. doi: 10.1016/j.ame- pre.2011.05.003.
Source

Prevention Research Collaboration, Sydney University, Sydney, Australia. adri- anb@health.usyd.edu.au
Abstract
BACKGROUND:

Recent epidemiologic evidence points to the health risks of prolonged sitting, that are independent of physical activity, but few papers have reported the descriptive epidemiology of sitting in popu- lation studies

[page131image13720]

with adults.
PURPOSE: This paper reports the prevalence of "high sitting time" and its correlates in an international study in 20 countries.

METHODS: Representative population samples from 20 countries were collected 2002-2004, and a question was asked on usual weekday hours spent sitting. This question was part of the International Prev- alence Study, using the International Physical Activity Questionnaire (IPAQ). The sitting measure has acceptable reliability and validity. Daily sitting time was compared among countries, and by age group, gender, educational attainment, and physical activity.

RESULTS:
Data were available for 49,493 adults aged 18-65 years from 20 countries. The median reported sitting time was 300 minutes/day, with an interquartile range of 180-480 minutes. Countries reporting the lowest amount of sitting included Portugal, Brazil, and Colombia (medians ≤180 min/day), whereas adults in Taiwan, Norway, Hong Kong, Saudi Arabia, and Japan reported the highest sitting times (medians ≥360 min/day). In adjusted analyses, adults aged 40-65 years were significantly less likely to be in the highest quintile for sitting than adults aged 18-39 years (AOR=0.796), and those with postschool education had higher sitting times compared with those with high school or less education (OR=1.349). Physical activity showed an inverse relationship, with those reporting low activity on the IPAQ three times more likely to be in the highest-sitting quintile compared to those reporting high physical activity.
CONCLUSIONS:
Median sitting time varied widely across countries. Assessing sitting time is an important new area for preventive medicine, in addition to assessing physical activity and sedentary behaviors. Population surveys that monitor lifestyle behaviors should add measures of sitting time to physi- cal activity surveillance. Moreover, the use of objective measures to capture the spectrum of sed- entary (sitting) and physical activity behaviors is encouraged, particularly in low- and middle- income

countries commencing new surveillance activities.
Copyright © 2011 American Journal of Preventive Medicine. All rights reserved.
PMID: 21767731

Sitting time in Germany: an analysis of socio-demographic and environmental correlates.

BMC Public Health. 2013 Mar 6;13:196. doi: 10.1186/1471-2458-13-196.
Wallmann-Sperlich B, Bucksch J, Hansen S, Schantz P, Froboese I. Source
Institute of Health Promotion and Clinical Movement Science, German Sports University, Köln, D-50933, Germany. wallmann@dshs-koeln.de

Abstract BACKGROUND:

Sedentary behaviour in general and sitting time in particular is an emerging global health concern. The aim of this study was to provide data on the prevalence of sitting time in German adults and to examine socio-demographic and environmental correlates of sitting time. METHODS:

A representative sample of German adults (n = 2000; 967 men, 1033 women; 49.3 ±17.6 years of age) filled in the Global Physical Activity Questionnaire, including one question on overall sitting time and answered questions about the neighbourhood environment, as well as concerning demo- graphics. Daily sitting time was stratified by gender, age group, BMI, educational and income level, as well as physical activity (PA). To identify socio-demographic and environmental corre- lates of sitting time, we used a series of linear regressions.

RESULTS:
The overall median was 5 hours (299 minutes) of sitting time/day and men sat longer than women (5 vs. 4 hours/day; p < 0.05). In both genders age and PA were negatively and the educational level positively

[page133image13800]

associated with sitting time. The level of income was not a correlate of sitting time in multivariate analyses. Sitting time was significantly positively associated with higher neigh- bourhood safety for women. The variance of the multivariate model ranged from 16.5% for men to 8.9% for women.

CONCLUSIONS:
The overall sitting time was unequally distributed in the German adult population. Our findings suggest implementing specific interventions to reduce sitting time for subgroups such as men, younger aged adults and adults with a higher education and lower PA. Future studies should enhance our understanding of the specific correlates of different types and domains of sitting in order to guide the development of effective public health strategies.
PMID: 23497070

10,000 steps per day compared to exercise

10,000 steps a more effective meaadage than 30 minutes/day. The effect of two different health messages on physical activity levels and health in sedentary overweight, middle-aged women

Sebely Pal,1 Cheryl Cheng,1 and Suleen Ho1
BMC Public Health. 2011; 11: 204.
Published online 2011 March 31. doi: 10.1186/1471-2458-11-204 PMCID: PMC3078883
Abstract
Background
Most public health guidelines recommend that adults need to participate in 30 minutes of moder- ate intensity physical activity on most days of the week to maintain good health. Achieving the recommended 30 minutes of exercise a day can be difficult in middle aged, overweight women.

This 12 week study evaluated whether a 10,000 steps per day message was more effective than a 30 minutes a day message in increasing

physical activity in low active, overweight women. Methods
Thirty participants were randomized into 2 groups: Group 1 was asked to undertake 30 minutes of walking/day, whereas Group 2 was asked to accumulate 10,000 steps/day using their pedometers. Results

Results showed that there were no changes in anthropometric and blood pressure measures between or within groups. However, the 10,000 step and the 30 minutes groups' daily average number of steps/day were significantly higher than baseline at week 6 (p = 0.038 and p = 0.039 respectively) and at week 12 (p = 0.028 and p = 0.038 respectively). At week 12, the 10,000 steps group were taking an average of 4616 steps per day more (43% increase) than at baseline and the 30 minutes group were taking an average of 2761 steps per day more (35% increase) than at base- line. There was a significant difference in the number of steps with the 10,000 steps group versus 30 minutes group at 12 weeks (p = 0.045).

Conclusions
This study found that low active, overweight women undertook significantly more physical activity when they had a daily 10,000 step goal using a pedometer, than when they were asked to achieve 30 minutes of walking/day. Therefore we suggest that a public health recommendation of "10,000 steps/day", rather than the "30 min/day" could be applied to promote increased physical activity in sedentary middle aged women.

Video Games

The energy expenditure of an activity-promoting video game compared to sedentary video games and TV watching.

Mitre N, Foster RC, Lanningham-Foster L, Levine JA. J Pediatr Endocrinol Metab. 2011;24(9- 10):689-95.
Source

Division of Pediatric Endocrinology and Metabolism, Mayo Clinic College of Medicine, Roches- ter, MN, USA. nmitre@cmh.edu

Abstract

BACKGROUND:
In the present study we investigated the effect of television watching and the use of activity-promoting video games on energy expenditure in obese and lean children.
METHODS:
Energy expenditure and physical activity were measured while participants were watching televi- sion, playing a video game on a traditional sedentary video game console, and while playing the same video game on an activity-promoting video game console.
RESULTS:
Energy expenditure was significantly greater than television watching and playing video games on a sedentary video game console when children played the video game on the activity-promoting console. When examining movement with accelerometry, children moved significantly more when playing the video game on the Nintendo Wii console. CONCLUSION:
Activity-promoting video games have shown to increase movement, and be an important tool to raise energy expenditure by 50% when compared to sedentary activities of daily living.
PMID: 22145458

Playing active video games increases energy expenditure in children.

Graf DL, Pratt LV, Hester CN, Short KR.Pediatrics. 2009 Aug;124(2): 534-40. Epub 2009 Jul 13. Source
bDepartment of Pediatrics, aCollege of Medicine, University of Oklahoma Health Sciences Cen- ter, Oklahoma City, USA.

Abstract OBJECTIVE:

[page136image12648]

To compare energy expenditure rates in children playing the physically active video games, Dance Dance Revolution (DDR) and Nintendo's Wii Sports in relation to treadmill walking. METHODS:
Energy expenditure, heart rate, step rate, and perceived exertion were measured in 14 boys and 9 girls (ages 10-13 years; BMI at 3-98th percentile for age and gender) while watching television at rest, playing DDR at 2 skill levels, playing Wii bowling and boxing, and walking at 2.6, 4.2, and 5.7 km/h. Arterial elasticity was measured at rest and immediately after gaming.

RESULTS:
Compared with watching television, energy expenditure while gaming or walking increased 2- to 3-fold. Similarly, high rates of energy expenditure, heart rate, and perceived exertion were elicited from playing Wii boxing, DDR level 2, or walking at 5.7 km/h. This occurred despite variations in step rate among activities, reflecting greater use of upper body during Wii play (lowest step rate) than during walking (highest step rate) or DDR play. Wii bowling and beginner level DDR elic- ited a 2-fold increase in energy expenditure compared to television watching. Large-artery elastic- ity declined immediately after both DDR and Wii. The change was inversely related to the increment in energy expenditure above rest achieved during the activity.
CONCLUSIONS:
Energy expenditure during active video game play is comparable to moderate-intensity walking. Thus, for children who spend considerable time playing electronic screen games for entertain- ment, physically active games seem to be a safe, fun, and valuable means of promoting energy expenditure.
PMID: 19596737

Energy expenditure of sedentary screen time compared with active screen time for children. Lanningham-Foster L, Jensen TB, Foster RC, Redmond AB, Walker BA, Heinz D, Levine JA. Source, Pediatrics. 2006 Dec;118(6):e1831-5.

Endocrine Research Unit, Mayo Clinic, 200 First St, SW, Rochester, MN

55905, USA.
Abstract
OBJECTIVE:
We examined the effect of activity-enhancing screen devices on children's energy expenditure compared with performing the same activities while seated. Our hypothesis was that energy expenditure would be significantly greater when children played activity-promoting video games, compared with sedentary video games.

METHODS:
Energy expenditure was measured for 25 children aged 8 to 12 years, 15 of whom were lean, while they were watching television seated, playing a traditional video game seated, watching television while walking on a treadmill at 1.5 miles per hour, and playing activity-promoting video games.
RESULTS:
Watching television and playing video games while seated increased energy expenditure by 20 +/ - 13% and 22 +/- 12% above resting values, respectively. When subjects were walking on the treadmill and watching television, energy expenditure increased by 138 +/- 40% over resting values. For the activity-promoting video games, energy expenditure increased by 108 +/- 40% with the EyeToy (Sony Computer Entertainment) and by 172 +/- 68% with Dance Dance Revolution Ultramix 2 (Konami Digital Entertainment).
CONCLUSIONS:
Energy expenditure more than doubles when sedentary screen time is converted to active screen time. Such interventions might be considered for obesity prevention and treatment.
PMID: 17142504

Virtual reality and interactive digital game technology: new tools to address obesity and diabetes. Skip Rizzo A, Lange B, Suma EA, Bolas M., J Diabetes Sci Technol. 2011 Mar 1;5(2):256-64.
Source

Institute for Creative Technologies, University of Southern California, Playa Vista, California, USA. arizzo@usc.edu
Abstract
The convergence of the exponential advances in virtual reality (VR)- enabling technologies with a growing body of clinical research and experience has fueled the evolution of the discipline of clinical VR. This article begins with a brief overview of methods for producing and delivering VR environments that can be accessed by users for a range of clinical health conditions. Interactive digital games and new forms of natural movement-based interface devices are also discussed in the context of the emerging area of exergaming, along with some of the early results from studies of energy expenditure during the use of these systems. While these results suggest that playing currently available active exergames uses significantly more energy than sedentary activities and is equivalent to a brisk walk, these activities do not reach the level of intensity that would match playing the actual sport, nor do they deliver the recommended daily amount of exercise for chil-

dren. However, these results provide some support for the use of digital exergames using the cur- rent state of technology as a complement to, rather than a replacement, for regular exercise. This may change in the future as new advances in novel full-body interaction systems for providing vigorous interaction with digital games are expected to drive the creation of engaging, low-cost interactive game-based applications designed to increase exercise participation in persons at risk for obesity.

© 2011 Diabetes Technology Society. PMID: 21527091

Effects of active video games on body composition: a randomized controlled trial.

Maddison R, Foley L, Ni Mhurchu C, Jiang Y, Jull A, Prapavessis H, Hohepa M, Rodgers A. Source
Clinical Trials Research Unit, University of Auckland, Auckland, New

[page139image15896]

Zealand. Abstract

BACKGROUND:
Sedentary activities such as video gaming are independently associated with obesity. Active video games, in which players physically interact with images on screen, may help increase physical activity and improve body composition.
OBJECTIVE:
The aim of this study was to evaluate the effect of active video games over a 6-mo period on weight, body composition, physical activity, and physical fitness.
DESIGN:
We conducted a 2-arm, parallel, randomized controlled trial in Auckland, New Zealand. A total of 322 overweight and obese children aged 10-14 y, who were current users of sedentary video games, were randomly assigned at a 1:1 ratio to receive either an active video game upgrade pack- age (intervention, n = 160) or to have no change (control group, n = 162). The primary outcome was the change from baseline in body mass index (BMI; in kg/m(2)). Secondary outcomes were changes in percentage body fat, physical activity, cardiorespiratory fitness, video game play, and food snacking.
RESULTS:
At 24 wk, the treatment effect on BMI (-0.24; 95% CI: -0.44, -0.05; P = 0.02) favored the intervention group. The change (±SE) in BMI from baseline increased in the control group (0.34 ± 0.08) but remained the same in the intervention group (0.09 ± 0.08). There was also evidence of a reduction in body fat in the intervention group (-0.83%; 95% CI: -1.54%, -0.12%; P = 0.02). The change in daily time spent playing active video games at 24 wk increased (10.03 min; 95% CI: 6.26, 13.81 min; P < 0.0001) with the intervention accompanied by a reduction in the change in daily time spent playing nonactive video games (-9.39 min; 95% CI: -19.38, 0.59 min; P = 0.06). CONCLUSION:
An active video game intervention has a small but definite effect on BMI

and body composition in overweight and obese children. This trial was registered in the Australian New Zealand Clinical Trials Registry at http://www.anzctr.org.au/ as ACTRN12607000632493.
Comment in

•Am J Clin Nutr. 2011 Oct;94(4):1155; author reply 1156. PMID: 21562081

The energy expenditure of an activity-promoting video game compared to sedentary video games and TV watching.

Mitre N, Foster RC, Lanningham-Foster L, Levine JA. J Pediatr Endocrinol Metab. 2011;24(9- 10):689-95.
Source
Division of Pediatric Endocrinology and Metabolism, Mayo Clinic College of Medicine, Roches- ter, MN, USA. nmitre@cmh.edu

Abstract

BACKGROUND:
In the present study we investigated the effect of television watching and the use of activity-promoting video games on energy expenditure in obese and lean children.
METHODS:
Energy expenditure and physical activity were measured while participants were watching television, playing a video game on a traditional sedentary video game console, and while playing the same video game on an activity-promoting video game console.
RESULTS:
Energy expenditure was significantly greater than television watching and playing video games on a sedentary video game console when children played the video game on the activity-promoting console. When examining movement with accelerometry, children moved significantly more when playing the video game on the Nintendo Wii console. CONCLUSION:
Activity-promoting video games have shown to increase movement, and

[page141image12920] [page141image13080]

be an important tool to raise energy expenditure by 50% when compared to sedentary activities of daily living.
PMID: 22145458

Playing active video games increases energy expenditure in children.

Graf DL, Pratt LV, Hester CN, Short KR.Pediatrics. 2009 Aug;124(2): 534-40. Epub 2009 Jul 13. Source
bDepartment of Pediatrics, aCollege of Medicine, University of Oklahoma Health Sciences Cen- ter, Oklahoma City, USA.

Abstract
OBJECTIVE:
To compare energy expenditure rates in children playing the physically active video games, Dance Dance Revolution (DDR) and Nintendo's Wii Sports in relation to treadmill walking. METHODS:
Energy expenditure, heart rate, step rate, and perceived exertion were measured in 14 boys and 9 girls (ages 10-13 years; BMI at 3-98th percentile for age and gender) while watching television at rest, playing DDR at 2 skill levels, playing Wii bowling and boxing, and walking at 2.6, 4.2, and 5.7 km/h. Arterial elasticity was measured at rest and immediately after gaming.
RESULTS:
Compared with watching television, energy expenditure while gaming or walking increased 2- to 3-fold. Similarly, high rates of energy expenditure, heart rate, and perceived exertion were elicited from playing Wii boxing, DDR level 2, or walking at 5.7 km/h. This occurred despite variations in step rate among activities, reflecting greater use of upper body during Wii play (lowest step rate) than during walking (highest step rate) or DDR play. Wii bowling and beginner level DDR elic- ited a 2-fold increase in energy expenditure compared to television watching. Large-artery elastic- ity declined immediately after both DDR and Wii. The change was inversely related to the increment in energy expenditure above rest achieved during the activity.
CONCLUSIONS:

Energy expenditure during active video game play is comparable to moderate-intensity walking. Thus, for children who spend considerable time playing electronic screen games for entertain- ment, physically active games seem to be a safe, fun, and valuable means of promoting energy expenditure.

PMID: 19596737

Pediatrics. 2006 Dec;118(6):e1831-5.
Energy expenditure of sedentary screen time compared with active screen time for children. Lanningham-Foster L, Jensen TB, Foster RC, Redmond AB, Walker BA, Heinz D, Levine JA. Source
Endocrine Research Unit, Mayo Clinic, 200 First St, SW, Rochester, MN 55905, USA.
Abstract
OBJECTIVE:
We examined the effect of activity-enhancing screen devices on children's energy expenditure compared with performing the same activities while seated. Our hypothesis was that energy expenditure would be significantly greater when children played activity-promoting video games, compared with sedentary video games.
METHODS:
Energy expenditure was measured for 25 children aged 8 to 12 years, 15 of whom were lean, while they were watching television seated, playing a traditional video game seated, watching television while walking on a treadmill at 1.5 miles per hour, and playing activity-promoting video games.
RESULTS:
Watching television and playing video games while seated increased energy expenditure by 20 +/ - 13% and 22 +/- 12% above resting values, respectively. When subjects were walking on the treadmill and watching television, energy expenditure increased by 138 +/- 40% over resting val- ues. For the activity-promoting video games, energy expenditure increased by 108 +/- 40% with the EyeToy (Sony Computer Entertainment) and by 172 +/- 68% with Dance Dance Revolution

Ultramix 2 (Konami Digital Entertainment).
CONCLUSIONS:
Energy expenditure more than doubles when sedentary screen time is converted to active screen time. Such interventions might be considered for obesity prevention and treatment.
PMID: 17142504

J Diabetes Sci Technol. 2011 Mar 1;5(2):256-64.
Virtual reality and interactive digital game technology: new tools to address obesity and diabetes. Skip Rizzo A, Lange B, Suma EA, Bolas M.
Source
Institute for Creative Technologies, University of Southern California, Playa Vista, California, USA. arizzo@usc.edu
Abstract
The convergence of the exponential advances in virtual reality (VR)- enabling technologies with a growing body of clinical research and experience has fueled the evolution of the discipline of clin- ical VR. This article begins with a brief overview of methods for producing and delivering VR environments that can be accessed by users for a range of clinical health conditions. Interactive digital games and new forms of natural movement-based interface devices are also discussed in the context of the emerging area of exergaming, along with some of the early results from studies of energy expenditure during the use of these systems. While these results suggest that playing currently available active exergames uses significantly more energy than sedentary activities and is equivalent to a brisk walk, these activities do not reach the level of intensity that would match playing the actual sport, nor do they deliver the recommended daily amount of exercise for chil-

dren. However, these results provide some support for the use of digital exergames using the cur- rent state of technology as a complement to, rather than a replacement, for regular exercise. This may change in the future as new advances in novel full-body interaction systems for

[page144image15480]

providing vigorous interaction with digital games are expected to drive the creation of engaging, low-cost interactive game-based applications designed to increase exercise participation in persons at risk for obesity.

© 2011 Diabetes Technology Society. PMID: 21527091 Type your paragraph here.