Changes In Sitting Time Research Articles

Longitudinal analysis of sitting time and impact on wellbeing and quality-of-life of sedentary workers.

Sitting time (ST) in the occupational domain has been linked to reduced wellbeing and quality-of-life. However, studies investigating the impact of reducing ST in these outcomes are scarce. An ancillary analysis using data from a RCT containing a 6-month sit-stand desk-based intervention, evaluated workers' changes in ST (objectively measured), and subjective wellbeing and quality-of-life. Two groups were created based on changes in ST. Independent and paired-sample T-tests were used to evaluate the differences between and within groups, and analysis of covariance (ANCOVA) was conducted to evaluate the effects of ST reduction in the outcomes. Our analyses indicated that 13 participants out of 38 reduced ST (-72min/day [±40.0; p < 0.001], while 25 participants slightly reduced or increased ST (+36.7 min/day [±40.3; p < 0.001]). Both groups had an improvement in quality-of-life scores, but only those who reduced ST improved subjective wellbeing (p = 0.028). Despite these results, no time*group interaction was found.

Association between Change in Sitting Time and Risk of Developing Hypertension: An 8-Year Longitudinal Follow-up Study with Cohort Data Analysis in Korea

Association between Change in Sitting Time and Risk of Developing Hypertension: An 8-Year Longitudinal Follow-up Study with Cohort Data Analysis in Korea

Joint Association of Change in Physical Activity and Sitting Time with Metabolic Syndrome Risk: A Prospective Cohort Study.

Background and Aims: The purpose of this study was to investigate the combined impact of variations in physical activity (PA) and sitting time (ST) on the risk of developing metabolic syndrome (MetS). Methods: This study was conducted on a cohort of adults from the general population, aged 40-69 years, who participated in the KOGES community-based cohort study over a span of 10 years. Changes in PA and ST were assessed using the results from PA questionnaires completed during baseline and follow-up surveys. The diagnosis of MetS was determined according to the criteria established by the International Diabetes Federation. To evaluate the combined effect of PA and ST changes on the incidence of MetS, we calculated hazard ratios and 95% confidence intervals using a Cox proportional hazards regression model. Result: The incidence of MetS was reduced by 39% (HR = 0.61, 95% CI = 0.46-0.82) for increased ST/increased PA and 26% (HR = 0.74, 95% CI = 0.58-0.94) for decreased ST/increased PA, compared with increased ST/decreased PA, respectively. In addition, this study confirmed that the combined impact of changes in PA and ST, based on the domain of PA, on the incidence of MetS varied. Conclusion: Changes in ST and PA are associated with the risk of developing MetS. These findings lay the groundwork for further research on the relationship between changes in PA, ST, and the occurrence of diseases.

Abstract 15294: Preliminary Results of the Sit Less Program for Patients With Coronary Artery Disease: A Pilot Randomized Controlled Trial

Introduction: Coronary artery disease (CAD) patients spend on average 10-14 hours per day sitting, which is higher than the recommended 8 hours of sitting. Independent of physical activity levels, higher levels of daily sitting are associated with adverse cardiometabolic outcomes. This study evaluated the feasibility and preliminary efficacy of a multi-technology-based Sit Less program in reducing sitting time (ST) and increasing breaks in ST in CAD patients. Methods: CAD patients were randomized to a control (n=8) or a 12-week Sit Less program (n=11). Sit Less included one in-person counseling session, a Fitbit, a smart water bottle (used to break prolonged ST via frequent restroom visits), and tailored weekly text messages. Feasibility was assessed via text message response rate and program satisfaction. Primary outcomes included changes in total daily ST, prolonged ST (total time spent in sitting bouts of &gt;30 mins and &gt;60 mins), and sit-to-stand transitions (all measured using activPAL). Cardiometabolic biomarkers included BMI, blood pressure, insulin, HbA1c, and lipids. Pre-post group differences were examined using independent t-tests. Results: All participants completed the study (15 male, 66±10yrs, mean ST = 10.4 hours/day). Out of the 11 Sit Less participants, 82% responded to all text messages and expressed satisfaction with the program. Significant pre-post group differences were found for total daily ST and prolonged ST (Figure 1). The Sit Less group had 36 minutes reduction in total ST and 3.4 more sit-to-stand transitions, while the control group had 47 minutes increase in total ST and 1 fewer sit-to-stand transitions. No significant differences in cardiometabolic markers were found within or between groups. Conclusion: The Sit Less program was feasible in CAD patients and the intervention reduced total and prolonged ST. Large-scale trials are needed to assess the program's effectiveness in reducing sitting and improving cardiometabolic outcomes.

Abstract 15: Change in Physical Activity and Sitting Time After Myocardial Infarction and Mortality Among Postmenopausal Women in the Women’s Health Initiative-Observational Study

Introduction: The natural history of myocardial infarction in women is different than in men. Evidence related to change in physical activity (PA) or sitting time (ST) after first myocardial infarction (MI) and the association with subsequent mortality in women is sparse. Hypothesis: We hypothesized that women who increased or maintained high PA levels ( &gt; 7.5 MET-hrs/wk ) following first MI would have lower subsequent risk of all-cause, coronary heart disease (CHD) and cardiovascular disease (CVD) mortality compared to women who remained inactive. We also hypothesized that women who decreased or maintained low levels of ST (&lt;7 hrs/d) following first MI would have lower risk of mortality compared to women who maintained high amounts of ST. Methods: We conducted a prospective analysis among postmenopausal women who experienced a confirmed post-baseline incident MI in the Women’s Health Initiative-Observational Study. The analysis included n = 877 women with PA and n = 514 women with ST assessed both prior to and after the MI. Recreational PA was self-reported at baseline and annually through year 8. ST was self-reported at baseline, year 3, and year 6. Change in PA and ST was calculated from time points immediately before and after MI. Change in PA and ST was assessed continuously and categorically. Categories for change in PA were: (1) active, maintained ≥ 7.5 MET-hrs/wk (equivalent to meeting current PA guidelines); (2) increased from &lt;7.5 to &gt; 7.5 MET-hrs/wk; (3) decreased from &gt; 7.5 to &lt;7.5 MET-hrs/wk; and (4) inactive, maintained &lt;7.5 MET-hrs/wk. Categories for change in ST were: (1) maintained &gt; 7 hrs/d; (2) increased from &lt;7 to &gt; 7 hrs/d; (3) decreased &gt; 7 to &lt;7 hrs/d; and (4) maintained &lt;7 hrs/d. The primary outcomes were all-cause, CHD and CVD mortality. Multivariable Cox proportional hazard models estimated hazard ratios (HR) and 95% confidence intervals (CI) adjusted for CVD risk factors, including congestive heart failure. Results: Compared to women who remained inactive (&lt; 7.5 MET-hrs/wk) following MI, the multivariable-adjusted HR’s of all-cause mortality were: 0.58 (0.37-0.90) for women who had been active and decreased physical activity; 0.37 (0.20-0.60) for women who had been inactive and increased activity to ≥ 7.5 MET-hrs/wk; and 0.50 (0.36-0.70) for women who remained active. Results were similar for CHD &amp; CVD mortality. In contrast, all-cause mortality did not differ by change in sitting following MI when examined categorically. Nonetheless, when examined continuously, a 1 hour/day increase in sitting time pre- to post-MI was associated with a 9% increased risk of all-cause mortality (HR=1.09, 95% CI: 1.03-1.15). Conclusions: Results suggest that increasing or maintaining physical activity and limiting sitting following a first MI may be important strategies for decreasing mortality in postmenopausal women.

The relationship between changes in sitting time and mortality in post-menopausal US women.

Prolonged sitting is linked to various deleterious health outcomes. The alterability of the sitting time (ST)-health relationship is not fully established however and warrants study within populations susceptible to high ST. We assessed the mortality rates of post-menopausal women from the Women's Health Initiative (WHI) observational study, a 15-year prospective study of post-menopausal women aged 50-79 years, according to their change in ST between baseline and year six. A total of 77 801 participants had information at both times on which to be cross-classified into the following: (i) high ST at baseline and follow-up; (ii) low ST at baseline and follow-up; (iii) increased ST and (iv) decreased ST. Cox regression was used to assess the relationship between all-cause, CVD and cancer mortality with change in ST. At the end of follow-up, there were 1855 deaths. Compared with high ST maintainers, low ST maintainers had a 51 and 48% lower risk of all-cause and cancer mortality, respectively. Reducing sitting also resulted in a protective rate of 29% for all-cause and 27% for cancer mortality. These results highlight not only the benefit of maintaining minimal ST, but also the utility of decreasing ST in older women, if current levels are high.

The Feasibility of Reducing Sitting Time in Overweight and Obese Older Adults.

Overweight and obese older adults have high sedentary time. We tested the feasibility and preliminary effects of a sedentary time reduction intervention among adults over age 60 with a body mass index over 27 kg/m2 using a nonrandomized one-arm design. Participants (N = 25, mean age = 71.4, mean body mass index = 34) completed an 8-week theory-based intervention targeting reduced total sitting time and increased sit-to-stand transitions. An inclinometer (activPAL) measured the primary outcomes, change in total sitting time and sit-to-stand transitions. Secondary outcomes included physical activity (ActiGraph GT3X+ accelerometer), self-reported sedentary behaviors, physical function (Short Physical Performance Battery), depressive symptoms (8-item Patient Health Questionnaire), quality of life (PROMIS), and study satisfaction. Paired t tests examined pre-post test changes in sitting time, sit-to-stand transitions, and secondary outcomes. Inclinometer measured sitting time decreased by 27 min/day (p < .05) and sit-to-stand transitions increased by 2 per day (p > .05), while standing time increased by 25 min/day (p < .05). Accelerometer measured sedentary time, light-intensity, and moderate-to-vigorous physical activity improved (all p values ≤ .05). Self-reported sitting time, gait speed, and depressive symptoms also improved (all p values < .05). Effect sizes were small. Study satisfaction was high. Reducing sitting time is feasible, and the intervention shows preliminary evidence of effectiveness among older adults with overweight and obesity. Randomized trials of sedentary behavior reduction in overweight and obese older adults, most of whom have multiple chronic conditions, may be promising.

Nine year changes in sitting time in young and mid-aged Australian women: Findings from the Australian Longitudinal Study for Women's Health

ObjectiveTo examine changes in sitting time (ST) in women over nine years and to identify associations between life events and these changes. MethodsYoung (born 1973–78, n=5215) and mid-aged (born 1946–51, n=6973) women reported life events and ST in four surveys of the Australian Longitudinal Study on Women's Health between 2000 and 2010. Associations between life events and changes in ST between surveys (decreasers ≥2h/day less, increasers ≥2h/day more) were estimated using generalized estimating equations. ResultsAgainst a background of complex changes there was an overall decrease in ST in young women (median change −0.48h/day, interquartile range [IQR]=−2.54, 1.50) and an increase in ST in mid-aged women (median change 0.43h/day; IQR=−1.29, 2.0) over nine years. In young women, returning to study and job loss were associated with increased ST, while having a baby, beginning work and decreased income were associated with decreased ST. In mid-aged women, changes at work were associated with increased ST, while retiring and decreased income were associated with decreased ST. ConclusionsST changed over nine years in young and mid-aged Australian women. The life events they experienced, particularly events related to work and family, were associated with these changes.

Continued Sedentariness, Change in Sitting Time, and Mortality in Older Adults

Prolonged sitting time (ST) is associated with higher mortality. However, previous studies used only a single measure of ST at baseline, so they could not directly assess the effect of continued exposure to high ST, or of changes in ST, on mortality. We prospectively assessed the association of continued sedentariness and of changes in ST for 2 yr with subsequent long-term all-cause mortality. This study was based on a prospective cohort of 2635 persons representative of the Spanish population 60 yr and older. ST was self-reported in 2001 and 2003. The median of ST was used as the cutoff to define excessive ST. Individuals were classified as consistently sedentary (> median in 2001 and 2003), newly sedentary (≤ median in 2001 and > median in 2003), formerly sedentary (> median in 2001 and ≤ median in 2003), and consistently nonsedentary (≤ median in 2001 and 2003). The association of ST in the period 2001-2003 with all-cause mortality from 2003 through 2011 was assessed with Cox regression and adjusted for the main confounders, including physical activity. Among the study participants, 846 died between 2003 and 2011. Compared with persons who were consistently sedentary, the hazard ratios (95% confidence interval) for mortality were 0.91 (0.76-1.10) in those who were newly sedentary, 0.86 (0.70-1.05) in formerly sedentary individuals, and 0.75 (0.62-0.90) in those who remained consistently nonsedentary. The results were similar across strata defined according to obesity, morbidity, functional limitations, or meeting recommendations for physical activity. Compared with older adults who were consistently sedentary during 2 yr, consistently nonsedentary individuals showed reduced all-cause mortality. Individuals who changed ST experienced an intermediate reduction in mortality.

Associations between sitting time and weight in young adult Australian women

Objective Sedentary behaviour may be a contributor to weight gain in today's young adult women, who are gaining weight faster than women in their mothers' generation. The aim was to examine the relationships between sitting time and weight in young women. Method Data were from women born in 1973–1978 who completed surveys in 2000, 2003 and 2006 for the Australian Longitudinal Study on Women's Health. Associations between concurrent changes in sitting-time and weight, and prospective associations between these variables, were examined using ANOVA and linear regressions, stratified by BMI-category in 2000 ( n = 5562). Results Among overweight and obese women, percentage weight change from 2000 to 2006 was higher in those whose sitting time increased (> 20%) than in those whose sitting time decreased (> 20%) over the same period ( p < 0.05). Conversely, percentage change in sitting time was significantly higher in those who gained weight (> 5%) than in those who lost weight (> 5%) ( p < 0.05). There were no prospective associations between (change in) sitting time and weight change, or between (change in) weight and change in sitting time. Conclusion The results confirm associations between concurrent changes in weight and changes in sitting time in overweight and obese women, but no prospective relationships were found.