Background: Evidence suggests that sedentary behaviour (SB) is associated with poor health outcomes. SB at any age may have significant consequences for health and well-being and interventions targeting SB are accumulating. Therefore, the need to review the effects of multicomponent, complex interventions that incorporate effective strategies to reduce SB are essential. Methods: A systematic review and meta-analysis were conducted investigating the impact of interventions targeting SB across the lifespan. Six databases were searched and two review authors independently screened studies for eligibility, completed data extraction and assessed the risk of bias and complexity of each of the included studies. Results: A total of 77 adult studies (n=62, RCTs) and 84 studies (n=62, RCTs) in children were included. The findings demonstrated that interventions in adults when compared to active controls resulted in non-significant reductions in SB, although when compared to inactive controls significant reductions were found in both the short (MD-56.86; 95%CI-74.10,-39.63; n=4632; I 2 83%) and medium-to-long term (MD-20.14; 95%CI-34.13,-6.16; n=4537; I 2 65%). The findings demonstrated that interventions in children when compared to active controls may lead to relevant reductions in daily sedentary time in the short-term (MD-59.90; 95%CI-102.16,-17.65; n=267; I 2 86%), while interventions in children when compared to inactive controls may lead to relevant reductions in the short-term (MD-25.86; 95%CI-40.77,-10.96; n=9480; I 2 98%) and medium-to-long term (MD-14.02; 95%CI-19.49,-8.55; n=41, 138; I 2 98%). The assessment of complexity suggested that interventions may need to be suitably complex to address the challenges of a complex behaviour such as SB, but demonstrated that a higher complexity score is not necessarily associated with better outcomes in terms of sustained long-term changes.

BackgroundOlder adults are the fastest growing segment of the world‘s population. Recent evidence indicates that excessive sitting time is harmful to health, independent of meeting the recommended moderate to vigorous physical activity (PA) guidelines. The SITLESS project aims to determine whether exercise referral schemes (ERS) can be enhanced by self-management strategies (SMSs) to reduce sedentary behaviour (SB), increase PA and improve health, quality of life and function in the long term, as well as psychosocial outcomes in community-dwelling older European citizens from four countries, within a three-armed pragmatic randomised controlled trial, compared with ERS alone and also with general recommendations about PA.MethodsA total of 1338 older adults will be included in this study, recruited from four European countries through different existing primary prevention pathways. Participants will be randomly allocated into an ERS of 16 weeks (32 sessions, 45–60 min per session), ERS enhanced by seven sessions of SMSs and four telephone prompts, or a control group. Outcomes will be assessed at baseline, month 4 (end of ERS intervention), month 16 (12 months post intervention) and month 22 (18 months post intervention). Primary outcomes will include measures of SB (time spent sedentary) and PA (counts per minute). Secondary outcomes will include muscle and physical function, health economics’ related outcomes, anthropometry, quality of life, social networks, anxiety and depressive symptoms, disability, fear of falling, executive function and fatigue. A process evaluation will be conducted throughout the trial. The full analysis set will follow an intention-to-treat principle and will include all randomised participants for whom a baseline assessment is conducted. The study hypothesis will be tested with mixed linear models with repeated measures, to assess changes in the main outcomes (SB and PA) over time (baseline to month 22) and between study arms.DiscussionThe findings of this study may help inform the design and implementation of more effective interventions to reduce SB and increase PA levels, and hence improve long-term health outcomes in the older adult population. SITLESS aims to support policy-makers in deciding how or whether ERS should be further implemented or restructured in order to increase its adherence, impact and cost-effectiveness.Trial registrationClinicalTrials.gov, NCT02629666. Registered 19 November 2015.Electronic supplementary materialThe online version of this article (doi:10.1186/s13063-017-1956-x) contains supplementary material, which is available to authorized users.

The present study aimed to assess the association between sedentary behavior and sarcopenia among adults aged ≥65 years. Cross-sectional data from the Study on Global Ageing and Adult Health were analyzed. Sarcopenia was defined as having low skeletal muscle mass and either a slow gait speed or a weak handgrip strength. Self-reported sedentary behavior was assessed as a continuous variable (hours per day) and also as a categorical variable (0–<4, 4–<8, 8–<11, ≥11 hours/day). Multivariable logistic regression was conducted to assess the association between sedentary behavior and sarcopenia. Analyses using the overall sample and country-wise samples were conducted. A total of 14,585 participants aged ≥65 years were included in the analysis. Their mean age was 72.6 (standard deviation, 11.5) years and 55% were females. Compared to sedentary behavior of 0–<4 hours/day, ≥11 hours/day was significantly associated with 2.14 (95% CI = 1.06–4.33) times higher odds for sarcopenia. The country-wise analysis showed that overall, a one-hour increase in sedentary behavior per day was associated with 1.06 (95% CI = 1.04–1.10) times higher odds for sarcopenia, while the level of between-country heterogeneity was low (I2 = 12.9%). Public health and healthcare practitioners may wish to target reductions in sedentary behavior to aid in the prevention of sarcopenia in older adults.

Background Sedentary behavior (SB) and physical activity (PA) are important determinants of health in older adults. This study aimed to describe the composition of accelerometer-measured SB and PA in older adults, to explore self-reported context-specific SB, and to assess sociodemographic and functional correlates of engaging in higher levels of SB in participants of a multicenter study including four European countries. Method One thousand three hundred and sixty community-dwelling older adults from the SITLESS study (61.8% women; 75.3 ± 6.3 years) completed a self-reported SB questionnaire and wore an ActiGraph accelerometer for 7 days. Accelerometer-determined compositional descriptive statistics were calculated. A fixed-effects regression analysis was conducted to assess the sociodemographic (country, age, sex, civil status, education, and medications) and functional (body mass index and gait speed) correlates. Results Older adults spent 78.8% of waking time in SB, 18.6% in light-intensity PA, and 2.6% in moderate-to-vigorous PA. Accelerometry showed that women engaged in more light-intensity PA and walking and men engaged in higher amounts of moderate-to-vigorous PA. Watching television and reading accounted for 47.2% of waking time. Older age, being a man, single, taking more medications, being obese and overweight, and having a slower gait speed were statistically significant correlates of more sedentary time. Conclusions The high amount of SB of our participants justifies the need to develop and evaluate interventions to reduce sitting time. A clinically relevant change in gait speed can decrease almost 0.45 percentage points of sedentary time. The distribution of context-specific sedentary activities by country and sex showed minor differences, albeit worth noting.