Daily Sitting Time Research Articles

Does SuperPark Make Children Less Sedentary? How Visiting a Commercial Indoor Activity Park Affects 7 to 12 Years Old Children's Daily Sitting and Physical Activity Time.

Commercial indoor activity parks provide children with a variety of entertaining physical activities. This study examined whether visiting SuperPark affects total daily sitting and physical activity time. The participants (8 girls and 7 boys, aged 10.3 ± 1.9 years, height 144.5 ± 11.8 cm, body mass index (BMI) 19.3 ± 3.0 kg/m2) wore a thigh-worn accelerometer during a normal week and were provided free tickets to visit SuperPark on at least one day. On average, the children spent 3.3 ± 1.2 h in SuperPark. During the visits the children had 0.9 h less sitting (0.7 ± 0.3 h, p = 0.000) and 0.9 h more moderate-to-vigorous physical activity (MVPA; 1.4 ± 0.6 h, p = 0.002) as compared to the reference periods on days without a SuperPark visit (1.6 ± 0.3 h sitting and 0.5 ± 0.4 h MVPA). During the days when visiting SuperPark, sitting time decreased 1.0 h (5.8 ± 0.9 h, p = 0.008) and MVPA increased 0.8 h (3.0 ± 1.0 h, p = 0.017) as compared to the reference days (6.8 ± 1.1 h sitting and 2.2 ± 0.8 h MVPA). The effects were more pronounced during weekdays than weekends. The children spent more than three hours in SuperPark on one visit, of which almost a half was MVPA. During the whole day, one hour of sitting was replaced with MVPA, suggesting that visiting SuperPark has the potential to improve health. Whether children continue visiting SuperPark and gain health benefits merits investigation.

The University Faculty Physical Activity Inventory (UFPAI): A Preliminary Assessment of Physical Activity among Faculty at a Private University

Physical activity (PA) is decreasing, with the work environment being particularly influential on reduction in PA. However, physically active lifestyles meeting or exceeding 150 minutes/week have been linked to reductions in multiple deleterious chronic health conditions. University educators are inundated with University work as well as promotional challenges that may act as barriers to achieving recommended daily levels of PA. Currently, very few research studies have evaluated PA among University faculty. Thus, the purpose of this exploratory investigation was to evaluate self-reported levels of PA among faculty members at Biola University. Eligible survey respondents (N = 138) were men (n = 72, 48.7 ± 11.7 years of age, 179.3 ± 8.5 centimeters in height, 86.3 ± 16.1 kilograms in weight, and an average body mass index (BMI) of 26.8 ± 4.6 kg/m2) and women (n = 66, 44.8 ± 11.7 years of age, 166.2 ± 8.2 centimeters in height, 69.3 ± 13.2 kilograms in weight, and an average body mass index (BMI) of 25.1 ± 4.8 kg/m2) faculty members from Biola University. Participants completed the International Physical Activity Questionnaire (IPAQ), using the SurveyMonkey® platform. Total daily sitting time and metabolic equivalent (MET) minute activity-specific (leisure, household, occupational, and transport) were calculated. One way ANOVAs revealed significant (p = 0.02) main effects for job title and total minutes of PA per week. The post-hoc analysis revealed that adjuncts were significantly more physically active than full professors. Although the only statistically significant differences were between adjuncts and full professors, we observed a downward trend in median physical activity. Independent measures t-tests revealed a significant (p = 0.004) difference between men and women for total minutes of PA per week. Women were significantly more physically active than men. Only 5.1% of faculty reported below 150 min of cumulative PA within a week. Total median PA for faculty was 3,133.5 MET*min/week. 52.9% of faculty reported a high categorical score above 3,000.0 MET*min/week of activity with a median of 4,757.0 MET*min/week. Of the four domains, leisure activity had the greatest median at 1,169.5 MET*min/week and active transport had the least at 462.0 MET*min/week. Faculty surveyed in this study exceeded the ACSM minimum weekly recommendations for PA and lower faculty ranks were the most active.

Association of sitting time and breaks in sitting with muscle mass, strength, function, and inflammation in community-dwelling older adults

To examine the association of sitting time and breaks in sitting time with muscle mass, strength, function, and inflammation in older Australians. Data from the thigh-worn activPAL3™ monitor (7-day continuous wear) was used to derive time spent sitting (hours) and total number of sit-stand transitions per day. Body composition (dual energy X-ray absorptiometry), lower-body muscle strength, function (timed up-and-go [TUG], 4-m gait speed, four square step test, 30-second sit-to-stand), and serum inflammatory markers (interleukin-[IL-6], IL-8, IL-10, tumor necrosis factor-alpha [TNF-α], and adiponectin) were measured. Multiple regression analyses, adjusted for age, sex, ethnicity, education, employment status, marital status, number of prescription medications, smoking status, vitamin D, and stepping time, were used to assess the associations. Data from 123 community-dwelling older adults (aged 65-84years, 63% female) were used. Total daily sitting time was associated with lower percentage lean mass (β [95%CI], - 1.70% [- 2.30, - 1.10]) and higher total body fat mass (2.92kg [1.94, 3.30]). More frequent breaks in sitting time were associated with a 45% reduced risk of having pre-sarcopenia (OR = 0.55; 95% CI 0.34, 0.91; model 1), defined as appendicular lean mass divided by BMI. No significant associations were observed for sitting time or breaks in sitting with measures of muscle strength, function, or inflammation. In older community-dwelling adults, greater sitting time was associated with a lower percentage lean mass, while more frequent breaks in sitting time were associated with lower odds of having pre-sarcopenia. This suggests that reducing sedentary time and introducing frequent breaks in sedentary time may be beneficial for improving body composition in healthy older adults.

Daily sitting time associated with the risk of metabolic syndrome in Korean adolescents.

This study aimed to investigate the relationship between daily sitting time and the risk of metabolic syndrome in Korean adolescents. Data from 486 adolescents aged 12-18 years were obtained from national surveys. Daily sitting time was measured using questionnaires and divided into three intervals: <8 h; 8-12 h; and ≥12 h. The mean daily sitting time and prevalence of positive metabolic components were 620.9±9.9 min/day and 45.5±2.7%, respectively. In a multivariate logistic regression analysis, adolescents who sat longer were more likely to have metabolic components (p<0.05), independent of age, sex, area of residence, sleeping time and body mass index. Longer daily sitting time appears to be associated with an increased risk of metabolic syndrome in adolescents. These findings highlight the need to focus on reducing sitting time for all adolescents, not just for those at risk of obesity.

Comparison of subjective and objective measures of office workers' sedentary time.

Sedentary behavior is an independent and prominent risk factor for chronic disease. Occupational sitting is likely to be the largest determinant of overall daily sitting time. Gathering accurate data on sedentary behaviors is essential to determine prevalence and effectiveness of interventions to reduce sedentary time. The purpose of this research was to determine whether self-reported sedentary time assessed by the Paffenbarger Physical Activity Questionnaire (PPAQ) and the Occupational Sitting and Physical Activity Questionnaire (OSPAQ) was related to objectively assessed sedentary time by the activPAL3 activity monitor. In the spring of 2015, 44 women employed full-time at Slippery Rock University participated in this study. Participants were predominantly Caucasian (95%), middle-aged (48 ± 10 years), and had an average BMI of 30.5 ± 8.2. A positive, weak correlation was found in sedentary time between the PPAQ (14.65 ± 2.77 h) and the activPAL3 (17.71 ± 1.46 h) over a 24 hour day (r = 0.253; p = 0.098; n = 44). Thirty-nine of the 44 participants significantly underestimated their sedentary time as compared to the activPAL3 (3.06 ± 2.76 h; p = 0.001). A positive, weak correlation was also found in sedentary time between the OSPAQ (5.96 ± 1.11 h) and the activPAL3 (5.69 ± 1.06 h) during the 8.5 hour work day (r = 0.100; p = 0.518; n = 44). Future studies examining sedentary behaviors should use caution when only considering the use of subjective recall surveys. This is especially true when self-reported behaviors are used to inform health promotion programs and create universal recommendations aimed to reduce sedentary time.

The efficacy of motivational counselling and SMS reminders on daily sitting time in patients with rheumatoid arthritis: a randomised controlled trial

ObjectivesThe aim of this report is to investigate the efficacy of an individually tailored, theory-based behavioural intervention for reducing daily sitting time, pain and fatigue, as well as improving health-related...

Adherence to national exercise guidelines by patients attending emergency departments: A multi-site survey.

The proportion of adults in Australia meeting or exceeding the national guidelines for physical activity has remained relatively static over the past 10 years. The research objective was to measure self-reported physical activity and sedentary behaviour among ED patients in accordance with Australia's current physical activity and sedentary behaviour guidelines, revised in 2014. A convenience sample of participants was recruited from three EDs in Melbourne between February and May 2016. Eligible participants were administered the International Physical Activity Questionnaire - Short Form plus researcher-derived questions. Participants were assessed as whether meeting the physical activity guidelines or not, using pre-defined criteria. The proportion of 18-64 year olds meeting all of the physical activity guidelines was 19.0% (95% confidence interval [CI] 15.2-22.8). A majority of participants (63.1%, 95% CI 58.5-67.7) met the aerobic component of the guidelines although only 28.9% (95% CI 24.5-33.3) of participants reported undertaking strength building exercises two or more times per week. Adults in the oldest age group were found to be less likely to engage in muscle strengthening exercises (23.3%, n = 30) than those in the youngest age group (40.0%, n = 60, P = 0.005). Average daily sitting time (minutes) did not differ between men (median = 300) and women (median = 360, P = 0.118). Overall adherence with physical activity guidelines is low among adults attending the ED. All adults need to be encouraged to undertake muscle strengthening activities, especially adults in older age groups.

Motivational counselling and SMS-reminders for reduction of daily sitting time in patients with rheumatoid arthritis: a descriptive randomised controlled feasibility study.

BackgroundPatients with rheumatoid arthritis (RA) spend a high proportion of their waking time in sedentary behaviour (SB) and have an increased risk of cardiovascular disease. Reduction of SB and increase in light intensity physical activity has been suggested as a means of improvement of health in patients with mobility problems. Short-term intervention studies have demonstrated that SB can be reduced by behavioural interventions in sedentary populations. To evaluate descriptively the feasibility of recruitment, randomisation, outcome assessments, retention and the acceptability of an individually tailored, theory-based behavioural intervention targeting reduction in daily sitting time in patients with RA.MethodsA randomised, controlled trial with two parallel groups. RA patients >18 years of age and Health Assessment Questionnaire (HAQ) score < 2.5 were consecutively invited and screened for daily leisure time sitting > 4 h. The 16-week intervention included 1) three individual motivational counselling sessions and 2) individual text message reminders aimed at reducing daily sitting time. The control group was encouraged to maintain their usual lifestyles. Outcomes were assessed at baseline and after the 16 week intervention. Daily sitting time was measured using an ActivPAL3TM activity monitor. The study was not powered to show superiority; rather the objective was to focus on acceptability among patients and clinical health professionals.ResultsIn total, 107 patients were invited and screened before 20 met eligibility criteria and consented; reasons for declining study participation were mostly flares, lack of time and co-morbidities. One patient from the control group dropped out before end of intervention (due to a RA flare). Intervention participants completed all counselling sessions. All procedures regarding implementation of the trial protocol were feasible. The daily sitting time was reduced on average by 0.30 h in the intervention group unlike the control group that tended to increase it by 0.15 h after 16 weeks.ConclusionsThis study shows that an individually tailored behavioural intervention targeting reduction of SB was feasible and acceptable to patients with RA.Trial registrationThe Danish Data Protection Agency (ref.nb. 711-1-08 - 20 March 2011), the Ethics Committee of the Capital Region of Denmark (ref.nb. H-2-2012-112- 17 October 2012), clinicaltrials.gov (NCT01969604 - October 17 2013, retrospectively registered).

Sitting time and obesity in a sample of adults from Europe and the USA

Background: Obesity is a risk factor for many chronic diseases and the prevalence is increasing worldwide. Research suggests that sedentary behaviour (sitting) may be related to obesity.Aim: To examine the association between sitting time and obesity, while controlling for physical activity, in a large international sample.Subjects and methods: In total, 5338 adults from the UK, USA, Germany, Spain, Italy, France, Portugal, Austria and Switzerland self-reported their total daily sitting time, physical activity, age, height and weight. BMI (kg/m2), total physical activity (MET-minutes/week) and sitting time (hours/day) were derived. Participants were grouped into quartiles based on their daily sitting time (<4, 4–≤6, 6–≤8 and >8 hours/day) and logistic regression models explored the odds of being obese vs normal weight for each sitting time quartile.Results: Participants in the highest sitting time quartile (≥8 hours/day) had 62% higher odds of obesity compared to participants in the lowest quartile (<4 hours/day) after adjustment for physical activity and other confounding variables (OR = 1.62, 95% CI = 1.24–2.12, p < .01).Conclusion: Sitting time is associated with obesity in adults, independent of physical activity. Future research should clarify this association using objective measures of sitting time and physical activity to further inform health guidelines.

A Cluster Randomized Controlled Trial to Reduce Office Workers' Sitting Time: Effect on Activity Outcomes.

This study aimed to evaluate the initial and long-term effectiveness of a workplace intervention compared with usual practice, targeting the reduction of sitting on activity outcomes. Office worksites (≥1 km apart) from a single organization in Victoria, Australia, were cluster randomized to intervention (n = 7) or control (n = 7). Participants were 231 desk-based office workers (5-39 participants per worksite) working at least 0.6 full-time equivalent. The workplace-delivered intervention addressed organizational, physical environment, and individual behavioral changes to reduce sitting time. Assessments occurred at baseline, 3 months, and 12 months, with the primary outcome participants' objectively measured (activPAL3 device) workplace sitting time (minutes per 8-h workday). Secondary activity outcomes were workplace time spent standing, stepping (light, moderate to vigorous, and total), and in prolonged (≥30 min) sitting bouts (hours per 8-h workday); usual duration of workplace sitting bouts; and overall sitting, standing, and stepping time (minutes per 16-h day). Analysis was by linear mixed models, accounting for repeated-measures and clustering and adjusting for baseline values and potential confounders. At baseline, on average, participants (68% women; mean ± SD age = 45.6 ± 9.4 yr) sat, stood, and stepped for 78.8% ± 9.5%, 14.3% ± 8.2%, and 6.9% ± 2.9% of work hours, respectively. Workplace sitting time was significantly reduced in the intervention group compared with the controls at 3 months (-99.1 [95% confidence interval = -116.3 to -81.8] min per 8-h workday) and 12 months (-45.4 [-64.6 to -26.2] min per 8-h workday). Significant intervention effects (all favoring intervention) were observed for standing, prolonged sitting, and usual sitting bout duration at work, as well as overall sitting and standing time, with no significant or meaningful effects observed for stepping. This workplace-delivered multicomponent intervention was successful at reducing workplace and overall daily sitting time in both the short term and the long term.

Physical activity recommendations from general practitioners in Australia. Results from a national survey

ObjectiveTo identify subgroups of Australian adults likely to receive physical activity advice from their general practitioner and to evaluate the content of the advice provided. MethodsParticipants (n=1,799), recruited from the Australian Health and Social Science panel, completed an online survey. Signal Detection Analysis was used to identify subgroups that were more/less likely to have received physical activity recommendations. ResultsOverall, 18% of participants received a physical activity recommendation from their general practitioner in the past 12 months and eight unique subgroups were identified. The subgroup with the highest proportion (54%) of participants reporting that they received a physical activity recommendation was those with poor physical and mental health‐related quality of life and an average daily sitting time of <11 hours. Other subgroups with high proportions of individuals receiving recommendations were characterised by higher weight and/or the presence of co‐morbidities. The most commonly prescribed physical activity type was aerobic activity. Few participants received specific physical activity advice. ConclusionsGeneral practitioners are incorporating physical activity promotion into their practice, but primarily as a disease management tool and with limited specificity. ImplicationsStrategies to assist Australian general practitioners to effectively promote physical activity are needed.

The Effects of Passive Cycling Exercise for 20 min on Cardiorespiratory Dynamics in Healthy Men [corrected

An increase in the incidence rate of cardiovascular disease is attributed to high daily sitting time, while a drop in risk of cardiovascular disease comes from a decrease in daily sitting time, rather than an increase in physical activity levels. Although short-duration passive exercise increases energy expenditure and blood flow, few studies have reported on the responses of cardiorespiratory dynamics to long-duration passive exercise. The purpose of this study was to consider the effect of long-duration passive exercise for 20 min on cardiorespiratory and muscle oxygen dynamics. Eight healthy men continuously performed passive exercise using a cycle ergometer for 20 min at 50 rpm. Changes in oxygen uptake, cardiac output and muscle oxygenation were measured during passive cycling exercise. The oxygen uptake at 1 min after the start of passive exercise was significantly increased, compared to resting level, but subsequently returned to the same as resting level. Cardiac output showed no change during passive cycling exercise. Tissue oxygen saturation increased after the start of passive exercise and subsequently maintained steady state. These results suggest that the effect of increases in energy expenditure was not maintained by passive exercise for 20 min. In addition, it is likely that passive cycling exercise for 20 min has an effect on peripheral circulation, although the exercise seems to have no effect on central circulation.

Sitting Time, Fidgeting, and All-Cause Mortality in the UK Women's Cohort Study.

Sedentary behaviors (including sitting) may increase mortality risk independently of physical activity level. Little is known about how fidgeting behaviors might modify the association. Data were from the United Kingdom (UK) Women's Cohort Study. In 1999-2002, a total of 12,778 women (aged 37-78 years) provided data on average daily sitting time, overall fidgeting (irrespective of posture), and a range of relevant covariates including physical activity, diet, smoking status, and alcohol consumption. Participants were followed for mortality over a mean of 12 years. Proportional hazards Cox regression models estimated the relative risk of mortality in high (versus low) and medium (versus low) sitting time groups. Fidgeting modified the risk associated with sitting time (p=0.04 for interaction), leading us to separate groups for analysis. Adjusting for covariates, sitting for ≥7 hours/day (versus <5 hours/day) was associated with 30% increased all-cause mortality risk (hazard ratio [HR]=1.30, 95% CI=1.02, 1.66) only among women in the low fidgeting group. Among women in the high fidgeting group, sitting for 5-6 hours/day (versus <5 hours/day) was associated with decreased mortality risk (HR=0.63, 95% CI=0.43, 0.91), adjusting for a range of covariates. There was no increased mortality risk from longer sitting time in the middle and high fidgeting groups. Fidgeting may reduce the risk of all-cause mortality associated with excessive sitting time. More detailed and better-validated measures of fidgeting should be identified in other studies to replicate these findings and identity mechanisms, particularly measures that distinguish fidgeting in a seated from standing posture.

Excessive sitting at work and at home: Correlates of occupational sitting and TV viewing time in working adults.

BackgroundRecent evidence links sedentary behaviour (or too much sitting) with poorer health outcomes; many adults accumulate the majority of their daily sitting time through occupational sitting and TV viewing. To further the development and targeting of evidence-based strategies there is a need for identification of the factors associated with higher levels of these behaviours. This study examined socio-demographic and health-related correlates of occupational sitting and of combined high levels of occupational sitting/TV viewing time amongst working adults.MethodsParticipants were attendees of the third wave (2011/12) of the Australian Diabetes, Obesity and Lifestyle (AusDiab) study who worked full-time (≥35 h/week; n = 1,235; 38 % women; mean ± SD age 53 ± 7 years). Logistic and multinomial logistic regression analyses were conducted (separately for women and men) to assess cross-sectional associations of self-reported occupational sitting time (categorised as high/low based on the median) and also the combination of occupational sitting time/TV viewing time (high/low for each outcome), with a number of potential socio-demographic and health-related correlates.ResultsHigher levels of occupational sitting (>6 h/day) were associated with higher household income for both genders. Lower levels of occupational sitting were associated with being older (women only); and, for men only, having a blue collar occupation, having a technical/vocational educational attainment, and undertaking more leisure-time physical activity (LTPA). Attributes associated with high levels of both occupational sitting and TV viewing time included white collar occupation (men only), lower levels of LTPA (both genders), higher BMI (men), and higher energy consumption (women).ConclusionsHigher household income (both genders) and professional/managerial occupations (men only) were correlates of high occupational sitting time, relative to low occupational sitting time, while health-related factors (lower LTPA, higher BMI – men, and higher energy consumption – women) were associated with high levels of both occupational sitting and TV viewing time, relative to low occupational sitting and low TV viewing time. These findings suggest possible high-risk groups that may benefit from targeted interventions. Further research is needed on potentially modifiable environmental and social correlates of occupational sitting time, in order to inform workplace initiatives.

Sitting time and physical activity after stroke: physical ability is only part of the story

Background: Understanding factors that influence the amount of time people with stroke spend sitting and being active is important to inform the development of targeted interventions.Objective: To explore the physical, cognitive, and psychosocial factors associated with daily sitting time and physical activity in people with stroke.Method: Secondary analysis of an observational study (n = 50, mean age 67.2 ± 11.6 years, 33 men) of adults at least 6 months post-stroke. Activity monitor data were collected via a 7-day, continuous wear (24 hours/day) protocol. Sitting time [total, and prolonged (time in bouts of ≥ 30 minutes)] was measured with an activPAL3 activity monitor. A hip-worn Actigraph GT3X+ accelerometer was used to measure moderate-to-vigorous-intensity physical activity (MVPA) time. Univariate analyses examined relationships of stroke severity (National Institutes of Health Stroke Scale), physical [walking speed, Stroke Impact Scale (SIS) physical domain score], cognitive (Montreal Cognitive Assessment), and psychosocial factors (living arrangement, SIS emotional domain score) with sitting time, prolonged sitting time, and MVPA.Results: Self-reported physical function and walking speed were negatively associated with total sitting time (r = − 0.354, P = 0.022 and r = − 0.361, P = 0.011, respectively) and prolonged sitting time (r = − 0.5, P = 0.001 and − 0.45, P = 0.001, respectively), and positively associated with MVPA (r = 0.469, P = 0.002 and 0.431, P = 0.003, respectively).Conclusions: Physical factors, such as walking ability, may influence sitting and activity time in people with stroke, yet much of the variance in daily sitting time remains unexplained. Large prospective studies are required to understand the drivers of activity and sitting time.

Total and domain‐specific sitting time among employees in desk‐based work settings in Australia

Objective:To describe the total and domain‐specific daily sitting time among a sample of Australian office‐based employees. Methods:In April 2010, paper‐based surveys were provided to desk‐based employees (n=801) in Victoria, Australia. Total daily and domain‐specific (work, leisure‐time and transport‐related) sitting time (minutes/day) were assessed by validated questionnaires. Differences in sitting time were examined across socio‐demographic (age, sex, occupational status) and lifestyle characteristics (physical activity levels, body mass index [BMI]) using multiple linear regression analyses. Results:The median (95% confidence interval [CI]) of total daily sitting time was 540 (531–557) minutes/day. Insufficiently active adults (median=578 minutes/day, [95%CI: 564–602]), younger adults aged 18–29 years (median=561 minutes/day, [95%CI: 540–577]) reported the highest total daily sitting times. Occupational sitting time accounted for almost 60% of total daily sitting time. In multivariate analyses, total daily sitting time was negatively associated with age (unstandardised regression coefficient [B]=−1.58, p<0.001) and overall physical activity (minutes/week) (B=−0.03, p<0.001) and positively associated with BMI (B=1.53, p=0.038). Conclusions:Desk‐based employees reported that more than half of their total daily sitting time was accrued in the work setting. Implications:Given the high contribution of occupational sitting to total daily sitting time among desk‐based employees, interventions should focus on the work setting.

The efficacy of motivational counseling and SMS-reminders on daily sitting time in patients with rheumatoid arthritis: protocol for a randomized controlled trial.

BackgroundPatients with RA (Rheumatoid Arthritis) are more sedentary than the general population. Reduction of Sedentary Behaviour (SB) has been suggested as a mean for improvement of health in patients with chronic diseases and mobility problems. Short-term intervention studies have demonstrated that SB can be reduced by behavioural interventions in healthy populations. However, it remains unexplored whether it is valid for patients with RA also.Therefore, the aim of this trial is to investigate the efficacy of an individually tailored, theory-based motivational counseling intervention on reducing daily sitting time in sedentary patients with RA. Additionally, to explore whether a reduction in daily sitting time is associated with reduced pain and fatigue, self-reported physical function, self-efficacy, improved health-related quality of life (HR-QoL) and cardiovascular biomarker levels, and finally to assess the cost-effectiveness of the intervention.Methods/DesignFor this parallel group randomized trial, 150 patients with RA and at least 5 hours of sitting time per day, will be recruited from a rheumatology outpatient clinic, and block-randomized to the intervention group or the control group receiving usual care. The intervention includes: 1) individual motivational counseling (in total 3 sessions) on reduction of daily sitting time in combination with 2) individual Short Text Message Service (SMS) reminders over a 16-week intervention period. Primary outcome is change in daily sitting time (minutes) from baseline to 16 weeks measured objectively using an ActivPAL® Activity Monitor. Secondary outcomes include fatigue, pain, physical function, HR-QoL, self-efficacy, costs and cost-effectiveness. Furthermore, anthropometric measures will be included as well as measurement of blood pressure and serum lipids. All outcomes are assessed at baseline and repeated after 16 weeks. Follow-up assessments are made at 6 and 18 months post-intervention.DiscussionThe intervention is simple, non-invasive and may be implemented at low costs. If the study confirms the positive results expected, the intervention might be implemented in clinical practice and potentially transferred to other clinical populations.Trial registrationClinicalTrial.gov registration number: NCT01969604. Date of registration: 17 October 2013.

Factors associated with daily sitting time in a rural community-dwelling of older adults from southern Brazil

The purpose of this study was to investigate the prevalence and associated factors with daily sitting time among older adults in a rural community in southern Brazil. This cross-sectional household-based study involved 477 subjects (≥ 60 years) of both sexes (2010-2011). Daily sitting time was estimated by questionnaire, and the sitting data were divided into two groups based on tertiles: (< 6 hours/day, and highest tertile: ≥ 6hours/day). The explanatory variables were: sex, age, schooling, living arrangements, occupation throughout life, currently working, number of morbidities, falls, nutritional status, cognitive status, smoking and alcohol consumption. The Poisson’s regression [prevalence ratio (PR) and confidence interval (CI) 95%] verified the association among explanatory variables and highest sitting tertile. According the results, the mean daily sitting time was 5.5 ± 3.2 hours/day. The proportion of older adults within the highest tertile of daily sitting time was 43.8%. Adjusted analyses showed that being older (PR 1.02, CI95%:1.01-1.04), being male (PR1.23, CI95%: 1.04-1.45), living with other people (PR 1.38, CI95%:1.02-1.86), having worked in agriculture (PR 1.24 CI95%: 1.04-1.48), and not working (PR1.21, CI95%:1.02-1.44), each were positively associated with highest terlile of daily sitting time. The illiterate older adults (PR=0.70; 95% CI=0.55 - 0.89), subjects who had never smoked (PR 0.60, CI95%: 0.46-0.78) and those underweight (PR 0.49, CI95%: 0.30-0.79) were less likely to be in the highest tertile of daily sitting time (inverse association). In conclusion, the socio-demographic and lifestyle-related variables are associated with the highest terlile of daily sitting time.

Sedentary behavior and prostate cancer risk in the NIH-AARP Diet and Health Study.

Sedentary behavior (sitting time) has been proposed as an independent risk factor for some cancers; however, its role in the development of prostate cancer has not been determined. We examined the prospective associations of self-reported daily sitting time and daily television/video viewing time with the risk of developing or dying from prostate cancer among 170,481 men in the NIH-AARP Diet and Health Study. We estimated HRs and 95% confidence intervals (CI) using Cox proportional hazards regression. Between 1996 and 2006, there were 13,751 incident (including 1,365 advanced) prostate cancer cases identified; prostate cancer mortality (through 2008) was 669. No strong or significant association with prostate cancer risk was seen in fully adjusted models for either daily sitting or television/video time. There were some suggestions of effect modification by body mass index (BMI; interaction for television/video time and BMI, P = 0.02). For total prostate cancer risk, television/video time was associated with a slightly elevated, but nonsignificant, increase amongst obese men (HR = 1.28; 95% CI, 0.98-1.69); a null association was observed amongst overweight men (HR = 1.04; 0.89-1.22); and, for men with a normal BMI, television/video time was associated with a nonsignificant risk decrease (HR = 0.82; 95% CI, 0.66-1.01). Similar patterns were observed for total daily sitting and television/video time in advanced prostate cancer and prostate cancer mortality. Sedentary behavior seems to play a limited role in the development of prostate cancer; however, we cannot rule out potential effect modification by BMI or the impact of measurement error on results.

Abstract P255: Genetic Variation in Chromosome 8p23 is Associated With Sedentary Behavior in Humans

Sedentary behavior, usually quantified as sitting time, has been shown to be associated with several adverse health outcomes, even among individuals who meet the current recommendations for physical activity. Both twin and family studies have shown that sedentary behavior aggregates in families and is a heritable trait. However, little is known about genes and DNA sequence variants that contribute to propensity to be sedentary. The purpose of our study was to conduct a genome-wide association study to identify genomic regions and DNA sequence variants associated with sedentary time. A total of 67,530 Caucasians (56% female, mean age 62.1 years [SD 12.5]) from the Kaiser Permanente Research Program on Genes, Environment, and Health (RPGEH) cohort were used for the discovery analyses. Other RPGEH ethnicities (African-Americans: N=2,500; East Asians: N=6,300; Hispanics: N=8,800) were used for replication studies. Information on daily sitting time outside of work was obtained by a questionnaire. A custom panel of 657,184 autosomal single nucleotide polymorphisms (SNPs) was genotyped using Affymetrix platform. Associations between sedentary time (dichotomized; cases 3 hours or more, controls less than 3 hours per day) and the SNPs were tested with PLINK logistic model using age, sex, BMI and admixture principal components as covariates. The strongest evidence of association was detected on chromosome 8p23.1. A total of 24 SNPs within a 1.34 Mb region were associated with sedentary time at genome-wide significance level (p&lt;5x10 -8 ), with SNP rs11774552 showing the peak association (OR=0.924, p= 1.7x10 -12 ). Sex-specific analyses confirmed that the associations were present both in men and women. The same SNPs were not associated with sedentary time in other ethnicities. However, SNP rs28754712, which is located in the immediate vicinity (+456 bp) of rs11774552, showed a significant association with sedentary time (OR=0.795, p=1.2x10 -3 ) in African-Americans. In summary, our results provide the first evidence of genomic region and DNA sequence variants associated with sedentary behavior in humans. If confirmed in additional replication studies, these findings will advance our understanding of biological mechanisms contributing to propensity to be sedentary.