Associations of meeting 24-hour movement behavior guidelines with social and emotional function in youth with ASD/ADHD

BACKGROUND

The 24-hour movement behavior (24-HMB) guidelines recommend that children and adolescents (youth) should limit screen time (ST), get an adequate amount of sleep (SL), and engage in sufficient physical activity (PA) to ensure health and healthy development. Meeting 24-HMB guidelines is associated with positive mental health outcomes (e.g., social and emotional function) in the general population. However, it is unclear whether such findings extend to youth with Autism Spectrum Disorder (ASD) and Attention-Deficit/Hyperactivity Disorder (ADHD). Thus, we examined associations of meeting 24-HMB guidelines with social and emotional function in youth with comorbid ASD/ADHD.

METHODS

Data from the 2020-2021 National Survey of Children's Health - a U.S. national, population-based, cross-sectional study - were used. We extracted and analyzed data on youth (aged between 6 and 17 years) diagnosed with comorbidity of ASD/ADHD. Data on movement behaviors (PA, ST, and SL) and specific outcome variables (social function and emotional function) were collected through caregiver-proxy reports. Logistic regressions were performed to examine the associations between meeting 24-HMB guidelines and social and emotional outcomes adjusting for covariates (e.g., age, sex, ethnicity, weight status, birth status, socio-economic status, and receiving medication/behavioral treatment).

RESULTS

Among 979 children and adolescents with comorbid ASD/ADHD, only 3.8 % met all three 24-HMB guidelines. In total, 45.0 % of participants met at least one guideline, and 25.5 % of those met at least two guidelines. Compared to those who did not meet any 24-HMB guidelines, meeting SL + ST guidelines was significantly associated with lower odds of poorer social function (being bullied: OR = 0.3, 95%CI [0.1-0.7]; arguing: OR = 0.2, 95%CI[0.1-0.4]). Furthermore, meeting PA + ST + SL guidelines was associated with lower odds of poorer emotional function (depression: OR = 0.5, 95%CI[0.3-0.7]).

CONCLUSION

Meeting 24-HMB guidelines was associated with better social and emotional function in U.S. youth with comorbid ASD/ADHD; however, currently very few with comorbid ASD/ADHD meet all 24-HMB guidelines. These results emphasize the importance of promoting adherence to the 24-HMB guidelines among youth facing the challenges of comorbid ASD/ADHD. These cross-sectional findings point to the need for further empirical evidence from longitudinal studies to support our conclusions.

Associations of meeting 24-hour movement behavior guidelines with prescribed eyeglasses/contact lenses among children and adolescents

BACKGROUND

Vision health is crucial for many aspects of life especially in developing populations such as children and adolescents. However, there is a high proportion of children and adolescents who suffer from visual impairments. Notably, accumulating evidence indicates that meeting the 24-hour movement behaviors (24-HMB) guidelines is associated with positive physical and mental health outcomes in children and adolescents. However, the relationship between being prescribed eyeglasses/contact lenses and meeting the 24-HMB guidelines has yet to be investigated. Thus, this study aimed to address this gap in the existing literature by using the 2021 National Survey of Children's Health (NSCH) dataset.

METHODS

In this cross-sectional study, data was retrieved from the 2021 NSCH. A total of 14,193 U.S. children and adolescents aged between 6 and 17 years were included for data analyses. We used items of the NSCH concerning the 24-HMB guidelines (i.e., physical activity, screen time, and sleep duration) and prescription of eyeglasses/contact lenses that were answered by the legal guardian of the children. Binary logistic regression was performed to investigate whether meeting the 24-HMB guidelines is associated with prescription eyeglasses/contact lenses and whether wearing eyeglasses/contact lenses predicts adherence to the 24-HMB guidelines among children and adolescents.

RESULTS

More than half of the participants (59.53%) wore eyeglasses/contact lenses and only 8.40% of them met all three of the 24-HMB guidelines. Compared to meeting none of the 24-HMB guidelines, meeting one (OR = 0.76, 95% CI = 0.62-0.93, p = 0.008), two (OR = 0.54, 95% CI = 0.43-0.67, p < 0.001), and all three 24-HMB guidelines (OR = 0.47, 95% CI = 0.34-0.64, p < 0.001) were associated with a lower risk of being prescribed eyeglasses/contact lenses among children and adolescents.

CONCLUSIONS

The findings of the current study provided evidence that the prevalence of U.S. children and adolescents aged between 6 and 17 years who wore eyeglasses/contact lenses was relatively high. Furthermore, meeting the 24-HMB guidelines was associated with a lower risk of being prescribed eyeglasses/contact lenses. Future studies focusing on the effects of 24-HMB interventions on vision health among children and adolescents are needed to better inform public health actions.

Associations of 24 h time-use compositions of sitting, standing, physical activity and sleeping with optimal cardiometabolic risk and glycaemic control: The Maastricht Study

AIMS/HYPOTHESIS

The associations of sitting, standing, physical activity and sleep with cardiometabolic health and glycaemic control markers are interrelated. We aimed to identify 24 h time-use compositions associated with optimal metabolic and glycaemic control and determine whether these varied by diabetes status.

METHODS

Thigh-worn activPAL data from 2388 participants aged 40-75 years (48.7% female; mean age 60.1 [SD = 8.1] years; n=684 with type 2 diabetes) in The Maastricht Study were examined. Compositional isometric log ratios were generated from mean 24 h time use (sitting, standing, light-intensity physical activity [LPA], moderate-to-vigorous physical activity [MVPA] and sleeping) and regressed with outcomes of waist circumference, fasting plasma glucose (FPG), 2 h plasma glucose, HbA1c, the Matsuda index expressed as z scores, and with a clustered cardiometabolic risk score. Overall analyses were adjusted for demographics, smoking, dietary intake and diabetes status, and interaction by diabetes status was examined separately. The estimated difference when substituting 30 min of one behaviour with another was determined with isotemporal substitution. To identify optimal time use, all combinations of 24 h compositions possible within the study footprint (1st-99th percentile of each behaviour) were investigated to determine those cross-sectionally associated with the most-optimal outcome (top 5%) for each outcome measure.

RESULTS

Compositions lower in sitting time and with greater standing time, physical activity and sleeping had the most beneficial associations with outcomes. Associations were stronger in participants with type 2 diabetes (p<0.05 for interactions), with larger estimated benefits for waist circumference, FPG and HbA1c when sitting was replaced by LPA or MVPA in those with type 2 diabetes vs the overall sample. The mean (range) optimal compositions of 24 h time use, considering all outcomes, were 6 h (range 5 h 40 min-7 h 10 min) for sitting, 5 h 10 min (4 h 10 min-6 h 10 min) for standing, 2 h 10 min (2 h-2 h 20 min) for LPA, 2 h 10 min (1 h 40 min-2 h 20 min) for MVPA and 8 h 20 min (7 h 30 min-9 h) for sleeping.

CONCLUSIONS/INTERPRETATION

Shorter sitting time and more time spent standing, undergoing physical activity and sleeping are associated with preferable cardiometabolic health. The substitutions of behavioural time use were significantly stronger in their associations with glycaemic control in those with type 2 diabetes compared with those with normoglycaemic metabolism, especially when sitting time was balanced with greater physical activity.

Relative associations of behavioral and physiological risks for cardiometabolic disease with cognition in bipolar disorder during mid and later-life: findings from the UK biobank

BACKGROUND

Cardiometabolic disease risk factors are disproportionately prevalent in bipolar disorder (BD) and are associated with cognitive impairment. It is, however, unknown which health risk factors for cardiometabolic disease are relevant to cognition in BD. This study aimed to identify the cardiometabolic disease risk factors that are the most important correlates of cognitive impairment in BD; and to examine whether the nature of the relationships vary between mid and later life.

METHODS

Data from the UK Biobank were available for 966 participants with BD, aged between 40 and 69 years. Individual cardiometabolic disease risk factors were initially regressed onto a global cognition score in separate models for the following risk factor domains; (1) health risk behaviors (physical activity, sedentary behavior, smoking, and sleep) and (2) physiological risk factors, stratified into (2a) anthropometric and clinical risk (handgrip strength, body composition, and blood pressure), and (2b) cardiometabolic disease risk biomarkers (CRP, lipid profile, and HbA1c). A final combined multivariate regression model for global cognition was then fitted, including only the predictor variables that were significantly associated with cognition in the previous models.

RESULTS

In the final combined model, lower mentally active and higher passive sedentary behavior, higher levels of physical activity, inadequate sleep duration, higher systolic and lower diastolic blood pressure, and lower handgrip strength were associated with worse global cognition.

CONCLUSIONS

Health risk behaviors, as well as blood pressure and muscular strength, are associated with cognitive function in BD, whereas other traditional physiological cardiometabolic disease risk factors are not.

Sedentary behavior and lifespan brain health

Higher levels of physical activity are known to benefit aspects of brain health across the lifespan. However, the role of sedentary behavior (SB) is less well understood. In this review we summarize and discuss evidence on the role of SB on brain health (including cognitive performance, structural or functional brain measures, and dementia risk) for different age groups, critically compare assessment approaches to capture SB, and offer insights into emerging opportunities to assess SB via digital technologies. Across the lifespan, specific characteristics of SB (particularly whether they are cognitively active or cognitively passive) potentially act as moderators influencing the associations between SB and specific brain health outcomes. We outline challenges and opportunities for future research aiming to provide more robust empirical evidence on these observations.

Sitting Time Reduction and Blood Pressure in Older Adults: A Randomized Clinical Trial

Importance

Practical health promotion strategies for improving cardiometabolic health in older adults are needed.

Objective

To examine the efficacy of a sedentary behavior reduction intervention for reducing sitting time and improving blood pressure in older adults.

Design, Setting, and Participants

This parallel-group randomized clinical trial was conducted in adults aged 60 to 89 years with high sitting time and body mass index of 30 to 50 from January 1, 2019, to November 31, 2022, at a health care system in Washington State.

Intervention

Participants were randomized 1:1 to the sitting reduction intervention or a healthy living attention control condition for 6 months. Intervention participants received 10 health coaching contacts, sitting reduction goals, and a standing desk and fitness tracker to prompt sitting breaks. The attention control group received 10 health coaching contacts to set general healthy living goals, excluding physical activity or sedentary behavior.

Main Outcomes and Measures

The primary outcome, measured at baseline, 3 months, and 6 months, was sitting time assessed using accelerometers worn for 7 days at each time point. Coprimary outcomes were systolic and diastolic blood pressure measured at baseline and 6 months.

Results

A total of 283 participants (140 intervention and 143 control) were randomized (baseline mean [SD] age, 68.8 [6.2] years; 186 [65.7%] female; mean [SD] body mass index, 34.9 [4.7]). At baseline, 147 (51.9%) had a hypertension diagnosis and 97 (69.3%) took at least 1 antihypertensive medication. Sitting time was reduced, favoring the intervention arm, with a difference in the mean change of -31.44 min/d at 3 months (95% CI, -48.69 to -14.19 min/d; P < .001) and -31.85 min/d at 6 months (95% CI, -52.91 to -10.79 min/d; P = .003). Systolic blood pressure change was lower by 3.48 mm Hg, favoring the intervention arm at 6 months (95% CI, -6.68 to -0.28 mm Hg; P = .03). There were 6 serious adverse events in each arm and none were study related.

Conclusions and Relevance

In this study of a 6-month sitting reduction intervention, older adults in the intervention reduced sedentary time by more than 30 min/d and reduced systolic blood pressure. Sitting reduction could be a promising approach to improve health in older adults.

Trial Registration

ClinicalTrials.gov Identifier: NCT03739762.

Associations of 24-hour movement behaviors with externalizing and internalizing problems among children and adolescents prescribed with eyeglasses/contact lenses

Background

Emerging evidence points towards the psychological benefits of meeting 24-hour movement behavior (24-HMB) guidelines, but such associations have not yet been investigated among children and adolescents of prescribed eyeglasses/contact lenses. To this end, we examined associations of meeting 24-HMB guidelines with internalizing and externalizing challenges in this population.

Methods

We used data from the 2021 National Survey of Children's Health, a cross-sectional survey including a representative sample of US children and adolescents. Data on movement behaviors (physical activity [PA], sedentary behavior operationalized via screen time [ST], and sleep duration [SL]) and internalizing and externalizing problems were collected through caregiver proxy reports. Caregivers completed questionnaires for 6030 (2799 girls) US children and adolescents of prescribed eyeglasses/contact lenses. Logistic regression analyses were conducted to determine the above-presented associations.

Results

Only 7.1 % of those prescribed eyeglasses/contact lenses met all three 24-HMB guidelines, while they were more likely to meet SL guideline alone (32.1 %) in relation to other independent guidelines including PA (2.5 %) and ST (10.9 %). Compared to not meeting any of the three 24-HMB guidelines, meeting at least two guidelines (25.22 %) was significantly linked to lower odds of internalizing problems and externalizing problems.

Conclusion

Meeting at least two components of the 24-HMB guidelines was beneficially linked to internalizing and externalizing problems. Thus, strategies or intervention programs that focus on meeting 24-HMB guidelines should be implemented among children and adolescents of those prescribed eyeglasses/contact lenses to foster coping with psychological issues.

Appropriately Addressing Too Much Sitting as a Public Health Issue: Content Analysis of Coverage in the Five Major National Japanese Newspapers

Recent international public health guidelines now address reducing and breaking up time spent sitting (sedentary behavior). Japanese people spend considerable time sitting in workplaces and other contexts. With potential future public health guidelines in Japan, there is the need for greater public awareness of the importance of reducing sedentary time and of practical ways to do so. From the five major Japanese national newspapers, articles on sedentary behavior published between 2000 and 2021 were identified and coded for content analysis, including the main topic of the article, population group, sedentary behavior context or domain, health outcome, and solutions for reducing sedentary time. There were 53 articles identified, with sedentary behavior being the main topic in 22; workers as a population group appeared in 20 articles and workplaces as a domain in 22. More than 70% mentioned health influences, but fewer than 60% mentioned solutions. Further to informing the public about adverse health influences and consequences for workers and workplaces, there is also the need for improved coverage of the broader benefits of reducing sitting time, sedentary behavior among older adults and children, sitting in all aspects of daily life, and, importantly, considering public health guidelines and solutions for reducing prolonged sitting.

Reallocating desk workers' sitting time to standing or stepping: associations with work performance

BACKGROUND

Studies have suggested that sitting time at work may lead to underperformance but they may underestimate the benefits to desk workers' performance of reducing occupational sitting time without considering the relative effects of the specific activities replaced.

AIMS

To estimate differences in work performance (presenteeism, absenteeism and engagement) when occupational sitting time is reallocated to standing/stepping in desk workers.

METHODS

Data for middle-aged desk workers were from a Japan-wide online survey (n = 2228). Self-report proportion of occupational sitting and standing/stepping, work hours and work performance indicators, including absolute (ratings relating only to self) and relative (ratings of self, compared to others) presenteeism and absenteeism, and dimensions of work engagement, were collected. Partition and isotemporal substitution models were used to investigate the associations of occupational sitting and standing/stepping time with work performance, including their reallocation effects.

RESULTS

In partition models, longer occupational sitting time was associated with a lower absolute presenteeism score (i.e. less productivity), lower absolute absenteeism (i.e. longer-than-expected work hours), and lower engagement. Longer occupational standing/stepping time was associated with lower absolute absenteeism and more engagement. Isotemporal substitution models showed that each hour of occupational sitting reallocated to standing/stepping was favourably associated with overall work engagement (B = 0.087; 95% confidence interval 0.051, 0.122) and its dimensions (B ranged from 0.078 to 0.092), but was not associated with presenteeism or absenteeism.

CONCLUSIONS

These findings suggest that management support and practical initiatives to encourage desk workers to replace portions of their sitting time with standing/stepping may contribute to enhanced work engagement.

Prioritizing a research agenda on built environments and physical activity: a twin panel Delphi consensus process with researchers and knowledge users

BACKGROUND

The growth of urban dwelling populations globally has led to rapid increases of research and policy initiatives addressing associations between the built environment and physical activity (PA). Given this rapid proliferation, it is important to identify priority areas and research questions for moving the field forward. The objective of this study was to identify and compare research priorities on the built environment and PA among researchers and knowledge users (e.g., policy makers, practitioners).

METHODS

Between September 2022 and April 2023, a three-round, modified Delphi survey was conducted among two independent panels of international researchers (n = 38) and knowledge users (n = 23) to identify similarities and differences in perceived research priorities on the built environment and PA and generate twin 'top 10' lists of the most important research needs.

RESULTS

From a broad range of self-identified issues, both panels ranked in common the most pressing research priorities including stronger study designs such as natural experiments, research that examines inequalities and inequities, establishing the cost effectiveness of interventions, safety and injuries related to engagement in active transportation (AT), and considerations for climate change and climate adaptation. Additional priorities identified by researchers included: implementation science, research that incorporates Indigenous perspectives, land-use policies, built environments that support active aging, and participatory research. Additional priorities identified by knowledge users included: built environments and PA among people living with disabilities and a need for national data on trip chaining, multi-modal travel, and non-work or school-related AT.

CONCLUSIONS

Five common research priorities between the two groups emerged, including (1) to better understand causality, (2) interactions with the natural environment, (3) economic evaluations, (4) social disparities, and (5) preventable AT-related injuries. The findings may help set directions for future research, interdisciplinary and intersectoral collaborations, and funding opportunities.

Changes in Desk-Based Workers' Sitting, Standing, and Stepping Time: Short- and Longer-Term Effects on Musculoskeletal Pain

PURPOSE

Sitting at work can be associated with musculoskeletal pain, but the effect of reductions in sitting is not well understood. We examined relationships with musculoskeletal pain of changes in sitting, standing, stepping, and short and long bouts of these behaviors.

METHODS

Analyses pooled data from 224 desk workers (68.4% women; mean ± SD age = 45.5 ± 9.4 yr; body mass index = 28.1 ± 6.1 kg⋅m -2 ) in intervention trial. Device-assessed (activPAL3) sitting, standing, and stepping time and multisite musculoskeletal pain (Nordic Questionnaire; 12 body areas) were assessed at baseline, 3 months, and 12 months. Compositional data analyses in linear mixed-effects regressions examined relationships within 16 waking hours of the behaviors and their short and long bouts, with changes from baseline in acute and chronic multisite musculoskeletal pain at 3 and 12 months. Analyses were adjusted for initial group randomization and relevant covariates.

RESULTS

At 3 months, increased standing relative to changes in other compositions was significantly associated with increased multisite musculoskeletal pain (acute: β = 1.54, 95% confidence interval [CI] = 0.10 to 2.98; chronic: β = 1.49, 95% CI = 0.12 to 2.83). By contrast, increased stepping relative to changes in other compositions was significantly associated with reduced multisite musculoskeletal pain (acute: β = -1.49, 95% CI = -2.97 to -0.02; chronic: β = -1.87, 95% CI = -3.75 to -0.01). Neither sitting reduction relative to changes in other compositions nor changes in short bouts relative to long bouts of the behaviors were significantly associated with multisite musculoskeletal pain changes. At 12 months, there were no significant associations for any of the compositional changes.

CONCLUSIONS

In the short term, while increasing standing with reduced sitting time can be unfavorable, concurrently increasing stepping could potentially reduce musculoskeletal pain. In the longer term, musculoskeletal pain may not be increased by moderate reductions in sitting time through spending more time standing or stepping.

Mentally-passive sedentary behavior and incident depression: Mediation by inflammatory markers

BACKGROUND

Sedentary behavior (SB; time spent sitting, as distinct from lack of exercise or physical activity) is associated with depression, yet little is known about the relationship between different types of SB (e.g., mentally-passive versus mentally-active) with depression and potential biological mediators of these associations.

METHODS

We used cohort data from the 1958 National Child Development Study (n = 4607; 50.4 % women), conducted in UK, employing the 44 y and 46 y waves as baseline, and the 50 y and 55 y waves as follow-up. Participants reported time spent in TV viewing and watching videos (mentally-passive SB); and, time sitting while doing light activities such as deskwork or driving a car during worktime (mentally-active SB). Depression diagnosis was self-reported during the initial and follow-up waves. Waist circumference, C-reactive protein, and glycated hemoglobin were examined as potential mediators.

RESULTS

Mentally-passive SB was associated with incident depression (HR: 1.43; 95%CI: 1.19; 1.71), while there was no association for mentally-active SB. Waist circumference (coefficient: -0.03; 95%CI: -0.05; -0.01; 9.2 %) and C-reactive protein (coefficient: -0.03; 95%CI: -0.04; -0.01; 8.3 %), but not glycated hemoglobin, partly mediated the association for mentally-passive SB.

CONCLUSIONS

In the relationship of mentally-passive SB with incident depression, the mediating contributions of waist circumference and C-reactive protein point to possible inflammatory-related mechanisms.

Physiology of sedentary behavior

Sedentary behaviors (SB) are characterized by low energy expenditure while in a sitting or reclining posture. Evidence relevant to understanding the physiology of SB can be derived from studies employing several experimental models: bed rest, immobilization, reduced step count, and reducing/interrupting prolonged SB. We examine the relevant physiological evidence relating to body weight and energy balance, intermediary metabolism, cardiovascular and respiratory systems, the musculoskeletal system, the central nervous system, and immunity and inflammatory responses. Excessive and prolonged SB can lead to insulin resistance, vascular dysfunction, shift in substrate use toward carbohydrate oxidation, shift in muscle fiber from oxidative to glycolytic type, reduced cardiorespiratory fitness, loss of muscle mass and strength and bone mass, and increased total body fat mass and visceral fat depot, blood lipid concentrations, and inflammation. Despite marked differences across individual studies, longer term interventions aimed at reducing/interrupting SB have resulted in small, albeit marginally clinically meaningful, benefits on body weight, waist circumference, percent body fat, fasting glucose, insulin, HbA1c and HDL concentrations, systolic blood pressure, and vascular function in adults and older adults. There is more limited evidence for other health-related outcomes and physiological systems and for children and adolescents. Future research should focus on the investigation of molecular and cellular mechanisms underpinning adaptations to increasing and reducing/interrupting SB and the necessary changes in SB and physical activity to impact physiological systems and overall health in diverse population groups.

Area-level socioeconomic inequalities in overweight and obesity: Systematic review on moderation by built-environment attributes

Residents of lower socioeconomic status (SES) areas are at a higher risk of overweight/obesity than those from higher SES areas. Built environment attributes may mitigate such inequalities. This systematic review synthesised findings of studies examining built environment attributes as potential moderators of the associations between area-level SES and overweight/obesity in adults. From five databases, nine eligible studies were identified. The SES-overweight/obesity relationship was stronger in inner areas and suburbs of large cities, while it was weaker in more rural areas. Two studies examined walkability and reported contrasting findings: no moderation in one and marginally significant moderation (less inequality in higher walkability areas) in the other. No evidence of moderation was found for street connectivity, population density, the food environment, access to physical activity facilities and several perceived environmental attributes. Further research is needed on other built environment attributes (e.g., access to, quantity and quality of green spaces, active transport features), and ideally using prospective study designs and objective makers of adiposity.

Neighborhood socioeconomic status and cardiometabolic risk: mediating roles of domain-specific physical activities and sedentary behaviors

PURPOSE

We examined the potential mediating roles of domain-specific physical activities and sedentary behaviors in the relationship between area-level socioeconomic status (SES) and cardiometabolic risk.

METHODS

Data were from the 2011/2012 Australian Diabetes, Obesity and Lifestyle study (n = 3431). The outcome was a clustered cardiometabolic risk (CCR) score, and the exposure was suburb-level SES. Potential mediators were domain-specific physical activities and sedentary behaviors. Multilevel linear regression models examined associations between SES and potential mediators (α) and between mediators and CCR (β). Mediation was assessed using the joint-significance test.

RESULTS

Higher SES was associated with a lower CCR score. Lower SES was associated with less frequent walking for transport, lower vigorous-intensity recreational physical activity, and higher TV time, which were associated with higher CCR scores. However, higher SES was associated with longer transport-related sitting time (all modes and in cars), which were associated with higher CCR scores.

CONCLUSIONS

The SES-cardiometabolic risk relationship may be partially explained by walking for transport, vigorous-intensity recreational physical activity, and TV viewing. These findings, which require corroboration from prospective evidence and clarification of the roles of transport-related sitting and occupational physical activity, can inform initiatives addressing socioeconomic inequalities in cardiometabolic health.

Area-level associations of travel behaviour metrics with waist circumference: findings from linkage of travel and health surveys

Individual-level analyses have consistently shown associations of travel behaviours with obesity-related measures. However, transport planning policies often target areas rather than individuals. To better inform transport-related policies and initiatives for obesity prevention, area-level relationships need to be investigated. This study linked data from two travel surveys with data from the Australian National Health Survey at the level of Population Health Areas (PHAs) and examined to what extent area-level travel behaviours metrics (prevalence of active travel, mixed travel and sedentary travel, diversity of travel modes) were associated with the rate of high waist circumference. Data from 51,987 travel survey participants were aggregated into 327 PHAs. Bayesian conditional autoregressive models were used to account for spatial autocorrelation. It was found that statistically replacing participants who relied on cars for travel (without walking/cycling) with those engaging in 30+ min/d of walking/cycling (without car use) was associated with a lower rate of high waist circumference. Areas with greater diversity of travel modes (mix of walking/cycling, car use, public transport use) also had lower prevalence of high waist circumference. This data-linkage study suggests that area-level transport planning strategies addressing car dependency, shifting car use to walking/cycling over 30 min/d, may help to reduce obesity.

Towards a core outcome set for cranioplasty following traumatic brain injury and stroke 'A systematic review of reported outcomes'

Background

There is wide-ranging published literature around cranioplasty following traumatic brain injury (TBI) and stroke, but the heterogeneity of outcomes limits the ability for meta-analysis. Consensus on appropriate outcome measures has not been reached, and given the clinical and research interest, a core outcome set (COS) would be beneficial.

Objectives

To collate outcomes currently reported across the cranioplasty literature which will subsequently be used in developing a cranioplasty COS.

Methods

This systematic review adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. All full-text English studies with more than ten patients (prospective) or more than 20 patients (retrospective) published after 1990 examining outcomes in CP were eligible for inclusion.

Results

The review included 205 studies from which 202 verbatim outcomes were extracted, grouped into 52 domains, and categorised into one or more of the OMERACT 2.0 framework core area(s). The total numbers of studies that reported outcomes in the core areas are 192 (94%) pathophysiological manifestations/ 114 (56%) resource use/economic impact/ 94 (46%) life impact/mortality 20 (10%). In addition, there are 61 outcome measures used in the 205 studies across all domains.

Conclusion

This study shows considerable heterogeneity in the types of outcomes used across the cranioplasty literature, demonstrating the importance and necessity of developing a COS to help standardise reporting across the literature.

Increased Prolonged Sitting in Patients with Rheumatoid Arthritis during the COVID-19 Pandemic: A Within-Subjects, Accelerometer-Based Study

BACKGROUND

Social distancing measures designed to contain the COVID-19 pandemic can restrict physical activity, a particular concern for high-risk patient groups. We assessed rheumatoid arthritis patients' physical activity and sedentary behavior level, pain, fatigue, and health-related quality of life prior to and during the social distancing measures implemented in Sao Paulo, Brazil.

METHODS

Post-menopausal females diagnosed with rheumatoid arthritis were assessed before (from March 2018 to March 2020) and during (from 24 May to 7 July 2020) social distancing measures to contain COVID-19 pandemic, using a within-subjects, repeated-measure design. Physical activity and sedentary behavior were assessed using accelerometry (ActivPAL micro). Pain, fatigue, and health-related quality of life were assessed by questionnaires.

RESULTS

Mean age was 60.9 years and BMI was 29.5 Kg/m². Disease activity ranged from remission to moderate activity. During social distancing, there were reductions in light-intensity activity (13.0% [-0.2 h/day, 95% CI: -0.4 to -0.04; p = 0.016]) and moderate-to-vigorous physical activity (38.8% [-4.5 min/day, 95% CI: -8.1 to -0.9; p = 0.015]), but not in standing time and sedentary time. However, time spent in prolonged bouts of sitting ≥30 min increased by 34% (1.0 h/day, 95% CI: 0.3 to 1.7; p = 0.006) and ≥60 min increased by 85% (1.0 h/day, 95% CI: 0.5 to 1.6). There were no changes in pain, fatigue, and health-related quality of life (all p > 0.050).

CONCLUSIONS

Imposed social distancing measures to contain the COVID-19 outbreak were associated with decreased physical activity and increased prolonged sedentary behavior, but did not change clinical symptoms sitting among patients with rheumatoid arthritis.

Device-measured sitting time and musculoskeletal pain in adults with normal glucose metabolism, prediabetes and type 2 diabetes-The Maastricht Study

BACKGROUND

Detrimental associations of sedentary behaviour (time spent sitting) with musculoskeletal pain (MSP) conditions have been observed. However, findings on those with, or at risk of, type 2 diabetes (T2D) have not been reported. We examined the linear and non-linear associations of device-measured daily sitting time with MSP outcomes according to glucose metabolism status (GMS).

METHODS

Cross-sectional data from 2827 participants aged 40-75 years in the Maastricht Study (1728 with normal glucose metabolism (NGM); 441 with prediabetes; 658 with T2D), for whom valid data were available on activPAL-derived daily sitting time, MSP [neck, shoulder, low back, and knee pain], and GMS. Associations were examined by logistic regression analyses, adjusted serially for relevant confounders, including moderate-to-vigorous intensity physical activity (MVPA) and body mass index (BMI). Restricted cubic splines were used to further examine non-linear relationships.

RESULTS

The fully adjusted model (including BMI, MVPA, and history of cardiovascular disease) showed daily sitting time to be significantly associated with knee pain in the overall sample (OR = 1.07, 95%CI: 1.01-1.12) and in those with T2D (OR = 1.11, 95%CI: 1.00-1.22); this was not statistically significant in those with prediabetes (OR = 1.04, 95%CI: 0.91-1.18) or NGM (OR = 1.05, 95%CI: 0.98-1.13). There were no statistically significant associations between daily sitting time and neck, shoulder, or low back pain in any of the models. Furthermore, the non-linear relationships were statistically non-significant.

CONCLUSION

Among middle-aged and older adults with T2D, daily sitting time was significantly associated with higher odds of knee pain, but not with neck, shoulder, or low back pain. No significant association was observed in those without T2D for neck, shoulder, low back, or knee pain. Future studies, preferably those utilising prospective designs, could examine additional attributes of daily sitting (e.g., sitting bouts and domain-specific sitting time) and the potential relationships of knee pain with mobility limitations.

CHAP-Adult: A Reliable and Valid Algorithm to Classify Sitting and Measure Sitting Patterns Using Data From Hip-Worn Accelerometers in Adults Aged 35

Background

Hip-worn accelerometers are commonly used, but data processed using the 100 counts per minute cut point do not accurately measure sitting patterns. We developed and validated a model to accurately classify sitting and sitting patterns using hip-worn accelerometer data from a wide age range of older adults.

Methods

Deep learning models were trained with 30-Hz triaxial hip-worn accelerometer data as inputs and activPAL sitting/nonsitting events as ground truth. Data from 981 adults aged 35-99 years from cohorts in two continents were used to train the model, which we call CHAP-Adult (Convolutional Neural Network Hip Accelerometer Posture-Adult). Validation was conducted among 419 randomly selected adults not included in model training.

Results

Mean errors (activPAL - CHAP-Adult) and 95% limits of agreement were: sedentary time -10.5 (-63.0, 42.0) min/day, breaks in sedentary time 1.9 (-9.2, 12.9) breaks/day, mean bout duration -0.6 (-4.0, 2.7) min, usual bout duration -1.4 (-8.3, 5.4) min, alpha .00 (-.04, .04), and time in ≥30-min bouts -15.1 (-84.3, 54.1) min/day. Respective mean (and absolute) percent errors were: -2.0% (4.0%), -4.7% (12.2%), 4.1% (11.6%), -4.4% (9.6%), 0.0% (1.4%), and 5.4% (9.6%). Pearson's correlations were: .96, .92, .86, .92, .78, and .96. Error was generally consistent across age, gender, and body mass index groups with the largest deviations observed for those with body mass index ≥30 kg/m2.

Conclusions

Overall, these strong validation results indicate CHAP-Adult represents a significant advancement in the ambulatory measurement of sitting and sitting patterns using hip-worn accelerometers. Pending external validation, it could be widely applied to data from around the world to extend understanding of the epidemiology and health consequences of sitting.

Built Environments and Cardiovascular Health: REVIEW AND IMPLICATIONS

PURPOSE

This review presents a general overview of the state of evidence on the relationships between neighborhood built environments and cardiovascular health outcomes among adults. We also summarize relevant literature on the associations of built environments with active living behaviors (physical activity [PA] and sedentary behavior), as they are considered as key behavioral pathways.

REVIEW METHODS

We identified recently published systematic reviews assessing associations of built environment attributes with cardiovascular health outcomes or active living behaviors. We summarized findings of the key systematic reviews and presented findings of pertinent empirical studies, where appropriate.

SUMMARY

Increasing evidence suggests that living in a place supportive of engaging in PA for transportation (eg, walkability features) and recreation (eg, parks) can be protective against cardiovascular disease (CVD) risk. Places conducive to higher levels of sedentary travel (ie, prolonged sitting in cars) may have adverse effects on cardiovascular health. The built environment of where people live can affect how active they are and subsequently their cardiovascular health. Clinical professionals are encouraged to consider the built environment features of where their patients live in counseling, as this may assist them to understand potential opportunities or barriers to active living and to propose a suitable CVD prevention strategy.

Psychological-health correlates of physical activity and sedentary behaviour during the COVID pandemic

BACKGROUND

While physical inactivity is associated with adverse psychological outcomes, less is known about the psychological outcomes associated with sedentary behaviour, and specifically, its mentally active and passive forms. The COVID-19 pandemic represents a unique opportunity to study associations between these variables in light of widespread stay-at-home mandates and restrictions on outdoor exercise/social activities. Using a cross-sectional dataset acquired during the COVID-19 pandemic in Australia, we examined whether physical activity and sedentary behaviour were associated with subjective quality of life (sQoL) and subjective cognitive dysfunction, and whether these associations were mediated by depressive symptoms.

METHODS

658 participants (males = 169, females = 489) self-reported data on physical activity and sedentary behaviour in an online survey during May 2020-May 2021. Data on physical activity and sedentary behaviour (both mentally active and passive types) was compared according to whether it was collected during or out of a lockdown period. Regression models were used to test associations of physical activity and sedentary behaviour with sQoL and subjective cognitive dysfunction, and whether these associations were mediated by depression severity.

RESULTS

Physical activity was beneficially associated with sQoL, whereas sedentary behaviour (both total hours and the reduction of mentally active/increase in mentally passive behaviour) was detrimentally associated with sQoL. These associations were mediated by depression severity. Physical activity and sedentary behaviour were also indirectly associated with subjective cognitive dysfunction by virtue of their associations with depression severity.

CONCLUSIONS

There are important differences in the psychological correlates of mentally passive and active sedentary behaviours. Our findings suggest that health promotion strategies should focus on not only increasing physical activity but also reducing passive sedentary behaviours as a means of maintaining good psychological health.

The built environment and mental health among older adults in Dalian: The mediating role of perceived environmental attributes

The basic attributes of the urban built environment are an important factor affecting mental health. However, research has rarely distinguished objective and perceived built environment characteristics to explore the associations with older adults' mental health. Based on data of 879 respondents aged 60 or older in Dalian, China, we explored the mediating roles of perceived built environmental attributes in the relationship between objective built environmental characteristics and mental wellbeing by structural equation modelling. Furthermore, to control for residential self-selection, the model was further tested by excluding the participants who self-selected their residences. The results showed that accessibility to daily living service facilities was positively associated with older adults' mental wellbeing through an indirect role of perceived built environmental attributes. The positive direct effect of aggregation of daily living service facilities on mental wellbeing was offset by the negative indirect effects of perceived built environmental attributes. In addition, the street interface density was negatively related to mental wellbeing through indirect effects. The diverse leisure, exercise and landscape facilities, underground parking and presence of elevators within neighborhoods were all positively associated with older adults' mental wellbeing through direct and/or indirect effects. The results were verified after excluding residential self-selection samples. These findings are helpful for evidence-based planning strategies and can provide guidelines on designing neighborhood landscapes and facilities which can further contribute to aging in place policies.

Preventing the adverse cardiovascular consequences of allogeneic stem cell transplantation with a multi-faceted exercise intervention: the ALLO-Active trial protocol

BACKGROUND

Allogeneic stem cell transplantation (allo-SCT) is a potentially lifesaving treatment for high-risk hematological malignancy, but survivors experience markedly elevated rates of cardiovascular disease and associated functional impairment. Mounting evidence suggests regular exercise, combined with a reduction in sedentary time through replacement with light exercise may be a useful therapeutic strategy for the prevention of cardiovascular comorbidities. However, this type of intervention has yet to be evaluated in patients undergoing allo-SCT. The ALLO-Active study will evaluate the efficacy of a ~ 4 month multi-faceted exercise intervention, commenced upon admission for allo-SCT, to preserve peak oxygen uptake (VO2peak) and peak cardiac output, compared with usual care. The study will also evaluate the effect of the intervention on functional independence, quality of life, and symptoms of fatigue.

METHODS

Sixty adults with hematological malignancy scheduled for allo-SCT will be randomly assigned to usual care (n = 30) or the exercise and sedentary behaviour intervention (n = 30). Participants assigned to the intervention will complete a thrice weekly aerobic and progressive resistance training program and concomitantly aim to reduce daily sedentary time by 30 min with short, frequent, light-intensity exercise bouts. Participants will undergo testing prior to, immediately after inpatient discharge, and 12 weeks after discharge. To address aim 1, VO2peak and peak cardiac output (multiple primary outcomes, p < 0.025) will be assessed via cardiopulmonary exercise testing and exercise cardiac magnetic resonance imaging, respectively. Secondary outcomes include functional independence (defined as VO2peak ≥ 18.mL.kg-1.min-1), quality of life, and fatigue (assessed via validated questionnaire). Exploratory outcomes will include indices of resting cardiac, vascular, and skeletal muscle structure and function, cardiovascular biomarkers, anxiety and depression, transplant outcomes (e.g., engraftment, graft-versus-host disease), and habitual physical activity, sedentary time, and sleep.

DISCUSSION

Multi-faceted exercise programs are a promising approach for ameliorating the cardiovascular consequences of allo-SCT. If this intervention proves to be effective, it will contribute to the development of evidence-based exercise guidelines for patients undergoing allo-SCT and assist with optimising the balance between acute cancer management and long-term health.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry (ANZCTR), ID: 12619000741189 . Registered 17 May 2019.

Linear and non-linear associations of device-measured sedentary time with older adults' skeletal muscle mass

BACKGROUND

Time spent sitting is associated adversely with health outcomes in older adults. Nevertheless, it is not clear how sedentary time may be related to appendicular skeletal muscle mass (ASM) - a key attribute of sarcopenia. This cross-sectional study examined associations of total sedentary time with ASM among community-dwelling older Japanese males and females.

METHODS

Participants (n = 281, 74.3 ± 5.2 yr) wore a tri-axial accelerometer for seven days. Body mass index-adjusted ASM (kg/BMI) was derived from bioimpedance measures. Multivariate linear and quadratic regression models examined the associations of ASM with total sedentary time, stratified by sex. Restricted cubic spline models were fitted to estimate non-linear associations. Isotemporal substitution (IS) models were used to estimate the impacts of replacing 30-minute of sedentary time with light physical activity (LPA) and moderate-to-vigorous physical activity (MVPA).

RESULTS

After adjustment, total sedentary time had a significant linear and negative association with ASM among females (β = -0.014; p = 0.023). For males, total sedentary time had a significant quadratic association (p = 0.020). Spline models indicated a reverse U-shaped association (p < 0.001) with total sedentary time over 9.3 h/day being associated with lower ASM. The IS models indicated that replacing 30 min/day of sedentary time with LPA would be positively and significantly associated with older females' ASM (β = 0.007, p = 0.022).

CONCLUSIONS

In older Japanese adults, higher volumes of time spent sedentary were associated with lower ASM. For males, only very high volumes of sedentary time appeared to be detrimental. These adverse relationships may in part be offset by more time spent in either LPA or MVPA.

Determining thresholds for spatial urban design and transport features that support walking to create healthy and sustainable cities: findings from the IPEN Adult study

An essential characteristic of a healthy and sustainable city is a physically active population. Effective policies for healthy and sustainable cities require evidence-informed quantitative targets. We aimed to identify the minimum thresholds for urban design and transport features associated with two physical activity criteria: at least 80% probability of engaging in any walking for transport and WHO's target of at least 15% relative reduction in insufficient physical activity through walking. The International Physical Activity and the Environment Network Adult (known as IPEN) study (N=11 615; 14 cities across ten countries) provided data on local urban design and transport features linked to walking. Associations of these features with the probability of engaging in any walking for transport and sufficient physical activity (≥150 min/week) by walking were estimated, and thresholds associated with the physical activity criteria were determined. Curvilinear associations of population, street intersection, and public transport densities with walking were found. Neighbourhoods exceeding around 5700 people per km², 100 intersections per km², and 25 public transport stops per km² were associated with meeting one or both physical activity criteria. Shorter distances to the nearest park were associated with more physical activity. We use the results to suggest specific target values for each feature as benchmarks for progression towards creating healthy and sustainable cities.

Start with reducing sedentary behavior: A stepwise approach to physical activity counseling in clinical practice

Recently, sedentary behavior recommendations have been included in the public health guidelines of multiple countries, pointing to new opportunities for prevention of chronic disease as well as a potential strategy for initiating long-term behavior change.

OBJECTIVE

To propose an evidence-informed approach to physical activity counseling that starts with a focus on reducing sedentary time.

METHODS

We put forward a case for addressing changes in sedentary behavior in clinical practice using a narrative review. We also propose a new approach for the assessment and counselling of patients with respect to movement behaviors.

RESULTS

There is evidence to support a stepwise approach to physical activity counseling that starts with targeting sedentary behavior, particularly in those who are highly sedentary, or those who have chronic disease, or physical impairments.

CONCLUSIONS

Our approach encourages clinicians to consider sedentary behavior counseling as a critical first step to physical activity counseling. For many patients, this initial step of reducing sedentary behavior could build a pathway to an active lifestyle.

PRACTICAL IMPLICATIONS

A shift from long periods of sedentary time to daily routines incorporating more light intensity physical activity could result in meaningful health improvements. Importantly, this approach may be more feasible for highly inactive patients.

Sitting less and moving more for improved metabolic and brain health in type 2 diabetes: 'OPTIMISE your health' trial protocol

Background

Clinical practice guidelines recommend that adults with type 2 diabetes (T2D) sit less and move more throughout the day. The 18-month OPTIMISE Your Health Clinical Trial was developed to support desk-based workers with T2D achieve these recommendations. The two-arm protocol consists of an intervention and control arms. The intervention arm receives 6 months health coaching, a sit-stand desktop workstation and an activity tracker, followed by 6 months of text message support, then 6 months maintenance. The control arm receives a delayed modified intervention after 12 months of usual care. This paper describes the methods of a randomised controlled trial (RCT) evaluating the effectiveness and cost-effectiveness of the intervention, compared to a delayed intervention control.

Methods

This is a two-arm RCT being conducted in Melbourne, Australia. Desk-based workers (≥0.8 full-time equivalent) aged 35–65 years, ambulatory, and with T2D and managed glycaemic control (6.5–10.0% HbA1c), are randomised to the multicomponent intervention (target n = 125) or delayed-intervention control (target n = 125) conditions. All intervention participants receive 6 months of tailored health coaching assisting them to “sit less” and “move more” at work and throughout the day, supported by a sit-stand desktop workstation and an activity tracker (Fitbit). Participants receive text message-based extended care for a further 6-months (6–12 months) followed by 6-months of non-contact (12–18 months: maintenance). Delayed intervention occurs at 12–18 months for the control arm. Assessments are undertaken at baseline, 3, 6, 12, 15 and 18-months. Primary outcomes are activPAL-measured sitting time (h/16 h day), glycosylated haemoglobin (HbA1c; %, mmol/mol) and, cognitive function measures (visual learning and new memory; Paired Associates Learning Total Errors [adjusted]). Secondary, exploratory, and process outcomes will also be collected throughout the trial.

Discussion

The OPTIMISE Your Health trial will provide unique insights into the benefits of an intervention aimed at sitting less and moving more in desk-bound office workers with T2D, with outcomes relevant to glycaemic control, and to cardiometabolic and brain health. Findings will contribute new insights to add to the evidence base on initiating and maintaining behaviour change with clinical populations and inform practice in diabetes management.

Trial registration

ANZCTRN12618001159246.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-022-13123-x.

Associations of park features with park use and park-based physical activity in an urban environment in Asia: A cross-sectional study

Park use is associated with health, yet our understanding of park features related to their use is limited. Singapore's parks were audited for 30 micro-features, then geospatial analysis characterized micro-features scores for parks nearest to participants' homes. Adults (3,435) reported their park use and park-based physical activity. Using linear regression models, we found living near a park with higher micro-features scores was associated with more time in parks and park-based physical activity. Specific micro-features were associated with more park time (wildlife areas, water features, forested areas, unpaved trails (2-2.6 h/month, p < 0.05)) and with physical activity in parks (water features, forested areas, large playground, open green spaces (1.8-2.2 h/month, p < 0.05)). These findings could inform parks planning to support population-health.

Television viewing time and all-cause mortality: interactions with BMI, physical activity, smoking, and dietary factors

Background

Higher levels of time spent sitting (sedentary behavior) contribute to adverse health outcomes, including earlier death. This effect may be modified by other lifestyle factors. We examined the association of television viewing (TV), a common leisure-time sedentary behavior, with all-cause mortality, and whether this is modified by body mass index (BMI), physical activity, smoking, alcohol intake, soft drink consumption, or diet-associated inflammation.

Methods

Using data from participants in the Melbourne Collaborative Cohort Study, flexible parametric survival models assessed the time-dependent association of self-reported TV time (three categories: < 2 h/day, 2–3 h/day, > 3 h/day) with all-cause mortality. Interaction terms were fitted to test whether there was effect modification of TV time by the other risk factors.

Results

From 19,570 participants, 4,417 deaths were reported over a median follow up of 14.5 years. More TV time was associated with earlier mortality; however, this relationship diminished with increasing age. The hazard ratio (HR) and 95% confidence interval (95% CI) for > 3 h/day compared with < 2 h/day of TV time was 1.34 (1.16, 1.55) at 70 years, 1.14 (1.04, 1.23) at 80 years, and 0.95 (0.84, 1.06) at 90 years. The TV time/mortality relationship was more evident in participants who were physically inactive (compared with active; p for interaction < 0.01) or had a higher dietary inflammatory index score (compared with a lower score; p for interaction = 0.03). No interactions were detected between TV time and BMI, smoking, alcohol intake, nor soft-drink consumption (all p for interaction > 0.16).

Conclusions

The relationship between TV time and all-cause mortality may change with age. It may also be more pronounced in those who are otherwise inactive or who have a pro-inflammatory diet.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12966-022-01273-5.

Impact on adolescent mental health of replacing screen-use with exercise: A prospective cohort study

BACKGROUND

Screen-based device use could increase the risk of adolescent depression. Distinct modalities of screen-use may have differential effects on mental health. We used compositional data analysis to examine how theoretically replacing different screen-uses with exercise might influence future adolescent emotional distress.

METHODS

In 4,599 adolescents (55% female) from a nationally-representative, prospective cohort, we used time-use diary data at age 14 to estimate daily screen use (television, social media, video game, general computer use) and exercise (team sport and individual exercise). The outcome was emotional distress at age 17, assessed using the emotional symptoms subscale of the Strengths and Difficulties Questionnaire.

RESULTS

Theoretically replacing 60 min of total screen time with exercise at age 14 was associated with a 0.05 (95%CI -0.08, -0.02) score reduction on the emotional symptoms' subscale at 17 in fully-adjusted models. Replacing 60 min of television or social media use with team sports was associated with a reduction of 0.17 (95%CI, -0.31, -0.04) and 0.15 (95%CI, -0.29, -0.01) in emotional symptom scores, respectively. We found no change in emotional symptom scores when replacing video game or general computer use with team sport, or when replacing any screen time with individual exercise.

LIMITATIONS

No direct measure of depressive symptoms at follow-up.

CONCLUSIONS

Replacing any screen time with exercise could reduce emotional distress, but the largest effect sizes were associated with replacing time in television watching and social media with team sports. Recommendations to limit screen-use in adolescents may require a nuanced approach for protecting mental health.

Trends in television viewing and overweight /obesity among Nepalese women: Findings from 2006, 2011 and 2016 Nepal Demographic and Health Surveys

BACKGROUND AND AIMS

Associations between overweight/obesity and television (TV) viewing have been identified in high-income countries, but little evidence is available from low- and middle-income countries. This study examined the trends and correlates of television viewing and overweight/obesity among Nepalese women between 2006 and 2016.

METHODS AND RESULTS

We analysed the data from 22,161 women aged 15-49 years who took part in Nepal Demographic Health Surveys 2006 (n = 10,115), 2011 (n = 5,881) or 2016 (n = 6,165). Trained staff collected data on TV viewing and sociodemographic attributes from a face-to-face survey while height and weight were measured objectively to determine body mass index. Around 38% of the study participants watched TV at least once a week in 2006, which increased to 49% in 2011 and 46% in 2016. The prevalence of overweight and obesity increased from 8% in 2006 to 14.6% in 2011 and 19.8% in 2016. Compared to those who did not watch TV at all, those watching it at least once a week were at 1.54 (95% CI: 1.02-2.33), 1.79 (95% CI: 1.23-2.60) and 1.46 (95% CI: 1.13-1.88) times higher odds of being overweight/obese in 2006, 2011 and 2016 respectively.

CONCLUSION

The prevalence of TV viewing rose among women in Nepal between 2006 and 2016 and was associated with overweight/obesity, which also increased dramatically over this period. Future studies examining the use of multiple screen devices, daily usage duration and content viewed are recommended to understand better the health impacts of transitions to more sedentary living in Nepal and similar settings.

Workplace neighbourhood built-environment attributes and sitting at work and for transport among Japanese desk-based workers

Workplace settings—both internal and external—can influence how workers are physically active or sedentary. Although research has identified some indoor environmental attributes associated with sitting at work, few studies have examined associations of workplace neighbourhood built-environment attributes with workplace sitting time. We examined the cross-sectional associations of perceived and objective workplace neighbourhood built-environment attributes with sitting time at work and for transport among desk-based workers in Japan. Data were collected from a nationwide online survey. The Abbreviated Neighborhood Environment Walkability Scale (n = 2137) and Walk Score® (for a subsample of participants; n = 1163) were used to assess perceived and objective built-environment attributes of workplace neighbourhoods. Self-reported daily average sitting time at work, in cars and in public transport was measured using a Japanese validated questionnaire. Linear regression models estimated the associations of workplace neighbourhood built-environment attributes with sitting time. All perceived workplace neighbourhood built-environment attributes were positively correlated with Walk Score®. However, statistically significant associations with Walk Score® were found for sitting for transport but not for sitting at work. Workers who perceived their workplace neighbourhoods to be more walkable reported a longer time sitting at work and in public transport but a shorter sitting time in cars. Our findings suggest that walkable workplace neighbourhoods may discourage longer car use but have workplaces where workers spend a long time sitting at work. The latter finding further suggests that there may be missed opportunities for desk-based workers to reduce sitting time. Future workplace interventions to reduce sitting time may be developed, taking advantage of the opportunities to take time away from work in workplace neighbourhoods.

Associations of COVID-19 lockdown restrictions with longer-term activity levels of working adults with type 2 diabetes (Preprint)

Background

Lockdown restrictions reduce COVID-19 community transmission; however, they may pose challenges for noncommunicable disease management. A 112-day hard lockdown in Victoria, Australia (commencing March 23, 2020) coincided with an intervention trial of reducing and breaking up sitting time in desk workers with type 2 diabetes who were using a provided consumer-grade activity tracker (Fitbit).

Objective

This study aims to compare continuously recorded activity levels preceding and during COVID-19 lockdown restrictions among working adults with type 2 diabetes participating in a sitting less and moving more intervention.

Methods

A total of 11 participants (n=8 male; mean age 52.8, SD 5 years) in Melbourne, Australia had Fitbit activity tracked before (mean 122.7, SD 47.9 days) and during (mean 99.7, SD 62.5 days) citywide COVID-19 lockdown restrictions. Regression models compared device (Fitbit Inspire HR)–derived activity (steps; metabolic equivalent tasks [METs]; mean time in sedentary, lightly, fairly, and very active minutes; and usual bout durations) during restrictions to prerestrictions. Changes in activity were statistically significant when estimates (Δ%) did not intercept zero.

Results

Overall, there was a decrease in mean steps (–1584 steps/day; Δ% –9%, 95% CI –11% to –7%); METs (–83 METs/day; Δ% –5%, 95% CI –6% to –5%); and lightly active (Δ% –4%, 95% CI –8% to –1%), fairly active (Δ% –8%, 95% CI –21% to –15%), and very active (Δ% –8%, 95% CI –11% to –5%) intensity minutes per day, and increases in mean sedentary minutes per day (51 mins/day; Δ% 3%, 95% CI 1%-6%). Only very active (+5.1 mins) and sedentary (+4.3 mins) bout durations changed significantly.

Conclusions

In a convenience sample of adults with type 2 diabetes, COVID-19 lockdown restrictions were associated with decreases in overall activity levels and increases in very active and sedentary bout durations. A Fitbit monitor provided meaningful continuous long-term data in this context.

Trial Registration

Australian New Zealand Clinical Trials Registry ACTRN12618001159246; https://anzctr.org.au/Trial/Registration/TrialReview.aspx?ACTRN=12618001159246

How supportive are workplace environments for sitting less and moving more? A descriptive study of Australian workplaces participating in the BeUpstanding program

•

Workplaces varied in the number of activity-supportive characteristics present.

•

Spatial characteristics were more common than resource or policy characteristics.

•

Characteristics absent in most workplaces were likely to be modifiable or low cost (“easy wins”).

•

Almost all workplaces had some room for improvement in terms of activity-supportive factors.

Desk-based workers are highly sedentary; this has been identified as an emerging work health and safety issue. To reduce workplace sitting time and promote physical activity it is important to understand what factors are already present within workplaces to inform future interventions. This cross-sectional study examined the prevalence of supportive environmental factors, prior to workplaces taking part in a ‘sit less, move more’ initiative (BeUpstanding). Participants were 291 Australian-based workplace champions (representing 230 organisations) who unlocked the BeUpstanding program’s online toolkit between September 2017 and mid-November 2020, and who completed surveys relating to champion characteristics, organisation and workplace characteristics, and the availability of environmental factors to support sitting less and moving more. Factors were characterized using descriptive statistics and compared across key sectors and factor categories (spatial; resources/initiatives; policy/cultural) using mixed logistic regression models. Of the 42 factors measured, only 11 were present in > 50% of workplaces. Spatial design factors were more likely to be present than resources/initiatives or policy/cultural factors. Centralised printers were the most commonly reported attribute (94%), while prompts to encourage stair use were the least common (4%). Most workplace factors with < 50% prevalence were modifiable and/or were considered modifiable with low cost. Organisations that were public sector, not small/medium, not regional/remote, and not blue-collar had higher odds of having supportive factors than their counterparts; however, workplaces varied considerably in the number of factors present. These findings can assist with developing and targeting initiatives and promoting feasible strategies for desk-based workers to sit less and move more.

Active Aging and Public Health: Evidence, Implications, and Opportunities

By 2050, 20% of the world's population will be over the age of 65 years, with projections that 80% of older adults will be living in low- to middle-income countries. Physical inactivity and sedentary time are particularly high in older adults, presenting unique public health challenges. In this article, we first review evidence that points to multiple beneficial outcomes of active aging, including better physical function, cognitive function, mental health, social health, and sleep and suggest the need to shift the research focus from chronic disease outcomes to more relevant outcomes that affect independence and quality of life. Second, we review the critical role of age-friendly environments in facilitating active aging equitably across different countries and cultures. Finally, we consider emerging opportunities related to social engagement and technology-enabled mobility that can facilitate active aging. In all these contexts, it is a priority to understand and address diversity within the global aging population. Expected final online publication date for the Annual Review of Public Health, Volume 43 is April 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

Musculoskeletal pain and sedentary behaviour in occupational and non-occupational settings: a systematic review with meta-analysis

BACKGROUND

Sedentary behaviour (SB; time spent sitting) is associated with musculoskeletal pain (MSP) conditions; however, no prior systematic review has examined these associations according to SB domains. We synthesised evidence on occupational and non-occupational SB and MSP conditions.

METHODS

Guided by a PRISMA protocol, eight databases (MEDLINE, CINAHL, PsycINFO, Web of Science, Scopus, Cochrane Library, SPORTDiscus, and AMED) and three grey literature sources (Google Scholar, WorldChat, and Trove) were searched (January 1, 2000, to March 17, 2021) for original quantitative studies of adults ≥ 18 years. Clinical-condition studies were excluded. Studies' risk of bias was assessed using the QualSyst checklist. For meta-analyses, random effect inverse-variance pooled effect size was estimated; otherwise, best-evidence synthesis was used for narrative review.

RESULTS

Of 178 potentially-eligible studies, 79 were included [24 general population; 55 occupational (incuding15 experimental/intervention)]; 56 studies were of high quality, with scores > 0.75. Data for 26 were meta-synthesised. For cross-sectional studies of non-occupational SB, meta-analysis showed full-day SB to be associated with low back pain [LBP - OR = 1.19(1.03 - 1.38)]. Narrative synthesis found full-day SB associations with knee pain, arthritis, and general MSP, but the evidence was insufficient on associations with neck/shoulder pain, hip pain, and upper extremities pain. Evidence of prospective associations of full-day SB with MSP conditions was insufficient. Also, there was insufficient evidence on both cross-sectional and prospective associations between leisure-time SB and MSP conditions. For occupational SB, cross-sectional studies meta-analysed indicated associations of self-reported workplace sitting with LBP [OR = 1.47(1.12 - 1.92)] and neck/shoulder pain [OR = 1.73(1.46 - 2.03)], but not with extremities pain [OR = 1.17(0.65 - 2.11)]. Best-evidence synthesis identified inconsistent findings on cross-sectional association and a probable negative prospective association of device-measured workplace sitting with LBP-intensity in tradespeople. There was cross-sectional evidence on the association of computer time with neck/shoulder pain, but insufficient evidence for LBP and general MSP. Experimental/intervention evidence indicated reduced LBP, neck/shoulder pain, and general MSP with reducing workplace sitting.

CONCLUSIONS

We found cross-sectional associations of occupational and non-occupational SB with MSP conditions, with occupational SB associations being occupation dependent, however, reverse causality bias cannot be ruled out. While prospective evidence was inconclusive, reducing workplace sitting was associated with reduced MSP conditions. Future studies should emphasise prospective analyses and examining potential interactions with chronic diseases.

PROTOCOL REGISTRATION

PROSPERO ID # CRD42020166412 (Amended to limit the scope).

Contrasting compositions of sitting, standing, stepping, and sleeping time: associations with glycaemic outcome by diabetes risk

BACKGROUND

Recent evidence suggests that prolonged sitting and its adverse impact on glycaemic indicators appear to be proportional to the degree of insulin resistance. To investigate this finding in a free-living context, we aimed to examine associations of device-measured 24-h time-use compositions of sitting, standing, stepping, and sleeping with fasting glucose (FPG) and 2 h post-load glucose (2hPLG) levels, and to examine separately the associations with time-use compositions among those at lower and at higher risk of developing type 2 diabetes.

METHODS

Cross-sectional analyses examined thigh-worn inclinometer data (activPAL, 7 day, 24 h/day protocol) from 648 participants (aged 36-80 years) at either lower (< 39 mmol/mol; < 5.7% HbA1c) or higher (≥39 mmol/mol; ≥5.7% HbA1c) diabetes risk from the 2011-2012 Australian Diabetes, Obesity and Lifestyle study. Multiple linear regression models were used to examine associations of differing compositions with FPG and 2hPLG, with time spent in each behaviour allowed to vary up to 60 min.

RESULTS

In general, the associations with the FPG within the time-use compositions were small, with statistically significant associations observed for sitting and sleeping (in the lower diabetes risk group) and standing (in higher diabetes risk group) only. For 2hPLG, statistically significant associations were observed for stepping only, with findings similar between lower (β = - 0.12 95%CI:-0.22, - 0.02) and higher (β = - 0.13 95%CI:-0.26, - 0.01) risk groups. Varying the composition had minimal impact on FPG; however 1 h less sitting time and equivalent increase in standing time was associated with attenuated FPG levels in higher risk only (Δ FPG% = - 1.5 95%CI: - 2.4, - 0.5). Large differences in 2hPLG were observed for both groups when varying the composition. One hour less sitting with equivalent increase in stepping was associated with attenuated 2hPLG, with estimations similar in lower (Δ 2hPLG% = - 3.8 95%CI: - 7.3, - 0.2) and higher (Δ 2hPLG% = - 5.0 95%CI: - 9.7, - 0.0) risk for diabetes.

CONCLUSIONS

In middle-aged and older adults, glycaemic control could be improved by reducing daily sitting time and replacing it with stepping. Standing could also be beneficial for those at higher risk of developing type 2 diabetes.

Acute cardiometabolic effects of brief active breaks in sitting for patients with rheumatoid arthritis

Exercise is a treatment in rheumatoid arthritis, but participation in moderate-to-vigorous exercise is challenging for some patients. Light-intensity breaks in sitting could be a promising alternative. We compared the acute effects of active breaks in sitting with those of moderate-to-vigorous exercise on cardiometabolic risk markers in patients with rheumatoid arthritis. In a crossover fashion, 15 women with rheumatoid arthritis underwent three 8-h experimental conditions: prolonged sitting (SIT), 30-min bout of moderate-to-vigorous exercise followed by prolonged sitting (EX), and 3-min bouts of light-intensity walking every 30 min of sitting (BR). Postprandial glucose, insulin, c-peptide, triglycerides, cytokines, lipid classes/subclasses (lipidomics), and blood pressure responses were assessed. Muscle biopsies were collected following each session to assess targeted proteins/genes. Glucose [-28% in area under the curve (AUC), P = 0.036], insulin (-28% in AUC, P = 0.016), and c-peptide (-27% in AUC, P = 0.006) postprandial responses were attenuated in BR versus SIT, whereas only c-peptide was lower in EX versus SIT (-20% in AUC, P = 0.002). IL-1β decreased during BR, but increased during EX and SIT (P = 0.027 and P = 0.085, respectively). IL-1ra was increased during EX versus BR (P = 0.002). TNF-α concentrations decreased during BR versus EX (P = 0.022). EX, but not BR, reduced systolic blood pressure (P = 0.013). Lipidomic analysis showed that 7 of 36 lipid classes/subclasses were significantly different between conditions, with greater changes being observed in EX. No differences were observed for protein/gene expression. Brief active breaks in sitting can offset markers of cardiometabolic disturbance, which may be particularly useful for patients who may find it difficult to adhere to exercise.NEW & NOTEWORTHY Exercise is a treatment in rheumatoid arthritis but is challenging for some patients. Light-intensity breaks in sitting could be a promising alternative. Our findings show beneficial, but differential, cardiometabolic effects of active breaks in sitting and exercise in patients with rheumatoid arthritis. Breaks in sitting mainly improved glycemic and inflammatory markers, whereas exercise improved lipidomic and hypotensive responses. Breaks in sitting show promise in offsetting aspects of cardiometabolic disturbance associated with prolonged sitting in rheumatoid arthritis.

Urban Densification and Physical Activity Change: A 12-Year Longitudinal Study of Australian Adults

Urbanization, a major force driving changes in neighborhood environments, may affect residents' health by influencing their daily activity levels. We examined associations of population density changes in urban areas with adults' physical activity changes over 12 years using data from the Australian Diabetes, Obesity and Lifestyle Study (1999-2012). The analytical sample contained 2,354 participants who remained at the same residential address throughout the study period in metropolitan cities and regional cities (42 study areas). Census-based population density measures were calculated for 1-km-radius buffers around their homes. Population density change was estimated using linear growth models. Two-level linear regression models were used to assess associations between changes in population density and changes in self-reported walking and physical activity durations. The average change in population density was 0.8% per year (range, -4.1 to 7.8) relative to baseline density. After adjustment for confounders, each 1% annual increase in population density was associated with 8.5-minutes/week (95% confidence interval: 0.6, 16.4) and 19.0-minutes/week (95% confidence interval: 3.7, 34.4) increases in walking and physical activity, respectively, over the 12-year study period. Increasing population density through urban planning policies of accommodating population growth within the existing urban boundary, rather than expanding city boundaries, could assist in promoting physical activity at the population level.

Sugar sweetened beverages and increasing prevalence of type 2 diabetes in the Indigenous community of Australia

AIMS

The aim of this viewpoint was to discuss a profound health gap in type 2 diabetes that exists between Indigenous and non-Indigenous Australians.

DATA SYNTHESIS

In Australia, type 2 diabetes is ranked as the fastest growing chronic condition, with the rates of type 2 diabetes higher among Indigenous than non-Indigenous Australians. Improvements to diet could aid in reducing overweight and obesity in the Indigenous community, with sugar sweetened beverages (SSBs) examples of discretionary foods that contain a high amount of sugar. The marked increase in type 2 diabetes, obesity and consumption of SSBs in the Indigenous community may suggest that type 2 diabetes may result from weight gain caused by SSB consumption. Recent evidence suggests that higher consumption of SSBs was associated with greater incidence of type 2 diabetes independent of adiposity. Some determinants influencing increased SSBs consumption in the Indigenous population include advertising, marketing, availability and affordability.

CONCLUSIONS

The prevalence rates of type 2 diabetes continue to be higher among Indigenous than non-Indigenous Australians and overall, a link between SSBs and risk of type 2 diabetes is reported. Three solutions to high SSBs consumption in Indigenous communities include increased availability, affordability, and accessibility of healthy food and drink, engagement of Indigenous people in offering solutions including discussion of a sugar tax on SSBs framed with Indigenous input, and the provision of clean community water supply and water bubblers.

Different frequencies of active interruptions to sitting have distinct effects on 22 h glycemic control in type 2 diabetes

BACKGROUND & AIMS

Whether the frequency of interruptions to sitting time involving simple resistance activities (SRAs), compared to uninterrupted sitting, differentially affected 22 h glycemic control in adults with medication-controlled type 2 diabetes (T2D).

METHODS & RESULTS

Twenty-four participants (13 men; mean ± SD age 62 ± 8 years) completed three 8 h laboratory conditions: SIT: uninterrupted sitting; SRA3: sitting interrupted with 3 min of SRAs every 30 min; and, SRA6: sitting interrupted with 6 min of SRAs every 60 min. Flash glucose monitors assessed glycemic control over a 22 h period. No differences were observed between conditions for overall 22 h glycemic control as measured by AUC_total, mean glucose and time in hyperglycemia. During the 3.5 h post-lunch period, mean glucose was significantly lower during SRA6 (10.1 mmol·L^-1, 95%CI 9.2, 11.0) compared to SIT (11.1 mmol·L^-1, 95%CI 10.2, 12.0; P = 0.006). Post-lunch iAUC_net was significantly lower during SRA6 (6.2 mmol·h·L^-1, 95%CI 3.3, 9.1) compared to SIT (9.9 mmol·h·L^-1, 95%CI 7.0, 12.9; P = 0.003). During the post-lunch period, compared to SIT (2.2 h, 95%CI 1.7, 2.6), time in hyperglycemia was significantly lower during SRA6 (1.5 h, 95%CI 1.0, 1.9, P = 0.001). Nocturnal mean glucose was significantly lower following the SRA3 condition (7.6 mmol·L^-1, 95%CI 7.1, 8.1) compared to SIT (8.1 mmol·L^-1, 95%CI 7.6, 8.7, P = 0.024).

CONCLUSIONS

With standardized total activity time, less-frequent active interruptions to sitting may acutely improve glycemic control; while more-frequent interruptions may be beneficial for nocturnal glucose in those with medication-controlled T2D.

882Relationship of Urban Sprawl with Overweight and Obesity: Roles of Physically-Active and Sedentary Travel Behaviours

Background

Urban sprawl – low-density neighbourhood developments at the city’s periphery – is related to risk of overweight/obesity. Our mediation analysis examined the extent to which this relationship may be explained by physically-active and sedentary travel behaviours.

Methods

We analysed data from 2,465 metropolitan residents in the 2011-12 wave of the Australian Diabetes, Obesity and Lifestyle Study. Urban sprawl measure was geographic information system derived residential proximity to the major city centre. Self-reported weekly frequency of walking for transport (WT) and car driving duration (car use) were used as measures of physically-active and sedentary travel behaviours. Risk of overweight/obesity was calculated using objectively-measured body mass index (&gt; 25 kg/m2). Multi-level regression models and joint-significance mediation tests were used.

Results

Residing near the city centre was associated with higher levels of WT and lower levels of car use. For instance, compared to those living within 10km from the city centre, those living over 30km away had 57% lower WT frequency (p&lt;0.001) and 1.4 hours/week more car use (p=0.002). In turn, lower levels of WT and higher levels car use were associated with elevated overweight/obesity risk.

Conclusions

These analyses suggest that travel behaviors can be potential mediators in relationships of urban sprawl with overweight/obesity. Future studies are warranted to assess causality of these relationships.

Key messages

Urban planning policies need to consider these impacts of the expansion of urban sprawl and promote inner-city high-density development by encouraging more physically-active travel and less time spent sitting in cars to reduce the population burden of overweight/obesity.

513Ophthalmic disease and older adults’ sedentary and physically-active behaviors: Findings from the NEIGE study

Background

Physical inactivity can be associated adversely with markers of eye health, but little is known about how ophthalmic disease (OD) may be related to sedentary behaviour (SB) and different intensities of physical activity in older adults. We compared device-assessed time spent in SB, light-intensity PA (LPA), and moderate-to-vigorous physical activity (MVPA) between older adults with and without OD.

Methods

A randomly-recruited sample of 512 community-dwelling older adults (47% male; aged 65–84 years) in Japan wore a valid tri-axial accelerometer for seven consecutive days in 2017. Prevalence of OD was assessed by medical interview. Times spent in SB, LPA, and MVPA were compared between those with and without OD by compositional multivariate analysis of covariance, adjusting for potential confounders (gender, age, residential area, living arrangement, working, body mass index, self-rated health, and cognitive function).

Results

Overall, percent times spent in SB, LPA, and MVPA during waking hours were 51.0, 44.6, and 4.4, respectively; and, 167 (36.5%) had OD. Activity patterns differed significantly between those with and without OD: in those with OD, the proportion of time spent in MVPA relative to other behaviours was lower, and the proportion of time spent in SB relative to other behaviours was higher.

Conclusions

Older adults with OD were found to be less physically active than those without.

Key messages

While these cross-sectional findings need to be confirmed by evidence from prospective studies, the reciprocal influences of OD and inactivity in older adults should be addressed as scientific, clinical and public health considerations.

The association of TV viewing time with 2-hour plasma glucose is modified by a prudent dietary pattern

BACKGROUND

TV viewing is associated with elevated plasma glucose, but it is not clear whether such associations can be modified by dietary patterns.

METHODS

We examined the interactions of TV viewing time and dietary patterns in relation to fasting and 2-hour plasma glucose. Cross-sectional analyses were performed among participants (N = 3081; 44.7% male; mean age 57.8 years) from the 2011 to 2012 Australian Diabetes, Obesity and Lifestyle Study (AusDiab) without clinically diagnosed diabetes or cardiovascular disease. Factor analysis (principal component) was conducted to identify dietary patterns. Multivariable linear regression models were used to examine distinct associations of TV viewing time and dietary patterns with fasting and 2-hour plasma glucose. Dichotomous TV viewing time (low: ≤ 2 h/d vs high: >2 h/d) and quartiles of dietary patterns were further combined to examine the joint associations with plasma glucose.

RESULTS

Three dietary patterns were identified: prudent, Western, and mixed. TV viewing time was positively associated (β = .01, P < .05) and the prudent dietary pattern was inversely associated (β = -.03, P < .05) with log transformed 2-hour plasma glucose. Compared with participants with high TV viewing/lowest prudent dietary pattern, participants with low TV viewing/highest prudent diet had the lowest 2-hour plasma glucose (β = -.05, P = .028). No interactions were found between TV viewing time and the Western dietary pattern, nor the mixed dietary pattern, in relation to either fasting or 2-hour plasma glucose.

CONCLUSIONS

Following a prudent dietary pattern may attenuate the adverse effect of TV viewing on 2-hour plasma glucose. Prospective studies and intervention trials are needed to further clarify these relationships.

Sedentary behaviour and bone health in older adults: a systematic review

Older adults spend more than 8 h/day in sedentary behaviours. Detrimental effects of sedentary behaviour (SB) on health are established, yet little is known about SB and bone health (bone mineral density; BMD) in older adults. The purpose of this review is to examine associations of SB with BMD in older adults. Five electronic databases were searched: Web of Science (Core Collection); PubMed; EMBASE; Sports Medicine and Education and PsycInfo. Inclusion criteria were healthy older adults mean age ≥ 65 years; measured SB and measured BMD using dual-energy X-ray absorptiometry. Quality was assessed using National Institute of Health Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies. After excluding duplicates 17813 papers were assessed; 17757 were excluded on title/abstract, 49 at full text, resulting in two prospective and five cross-sectional observational studies reviewed. Four were rated 'good' and three were rated 'fair' using the quality assessment criteria. Findings varied across the studies and differed by gender. In women, four studies reported significant positive associations of SB with BMD at different sites, and two found significant negative associations. Five studies which examined both men and women, men reported negative or no associations of SB with femoral neck, pelvic, whole body, spine or leg BMD. Whilst these findings suggest differences between men and women in the associations of SB with BMD, they may be due to the varying anatomical sections examined for BMD, the different methods used to measure SB, the varied quality of the studies included and the limited number of published findings.

Descriptive Epidemiology of Interruptions to Free-Living Sitting Time in Middle-Age and Older Adults

National guidelines recommend physically active interruptions to sitting time, however, the characteristics of these interruptions are broadly stated and ill-defined. A robust methodology for population surveillance for such interruptions is needed.

PURPOSE

To describe the frequency and characteristics (i.e., duration, stepping time, and estimated intensity) of all interruptions and physically active interruptions to adults' free-living sitting time (i.e., transitions from sitting to upright posture) across segments of the population.

METHODS

Australian Diabetes, Obesity and Lifestyle (AusDiab) study participants (321 men; 406 women; mean ± SD 58.0 ± 10.3 years) wore the activPAL3TM for ≥1 valid day. The characteristics of interruptions from laboratory studies demonstrating health benefits were selected to define active interruptions (≥5 min upright and/or ≥ 2 min stepping) and ambulatory interruptions (≥2 min stepping). The frequency and characteristics of all, active, and ambulatory interruptions were described and compared by age, gender, diabetes status, and body mass index.

RESULTS

Adults averaged 55.0 ± 21.8 interruptions per day, but only 20.3 ± 6.7 were active and 14.0 ± 5.4 were ambulatory. Median (25th, 75th percentile) duration was 2.6 (0.9, 7.8) minutes, stepping time was 0.8 (0.3, 2.0) minutes, and estimated energy expenditure was 4.3 (1.4, 12.5) MET-min. Those who were older, had obesity, or had diabetes had significantly (p < 0.05) fewer interruptions of all types and less stepping time during active interruptions than their counterparts (Cohen's d < 0.2).

CONCLUSION

Free-living interruptions were often less active than interruptions performed in effective acute laboratory studies and their content varied widely between population groups. Monitoring all interruptions as well as those that are more active is advisable to provide a comprehensive understanding of free-living sedentary behavior.

Frequency of Interruptions to Sitting Time: Benefits for Postprandial Metabolism in Type 2 Diabetes

OBJECTIVE

To determine whether interrupting sitting with brief bouts of simple resistance activities (SRAs) at different frequencies improves postprandial glucose, insulin, and triglycerides in adults with medication-controlled type 2 diabetes (T2D).

RESEARCH DESIGN AND METHODS

Participants (n = 23, 10 of whom were female, with mean ± SD age 62 ± 8 years and BMI 32.7 ± 3.5 kg · m^-2) completed a three-armed randomized crossover trial (6- to 14-day washout): sitting uninterrupted for 7 h (SIT), sitting with 3-min SRAs (half squats, calf raises, gluteal contractions, and knee raises) every 30 min (SRA3), and sitting with 6-min SRAs every 60 min (SRA6). Net incremental areas under the curve (iAUC_net) for glucose, insulin, and triglycerides were compared between conditions.

RESULTS

Glucose and insulin 7-h iAUC_net were attenuated significantly during SRA6 (glucose 17.0 mmol · h · L^-1, 95% CI 12.5, 21.4; insulin 1,229 pmol · h · L^-1, 95% CI 982, 1,538) in comparison with SIT (glucose 21.4 mmol · h · L^-1, 95% CI 16.9, 25.8; insulin 1,411 pmol · h · L^-1, 95% CI 1,128, 1,767; P < 0.05) and in comparison with SRA3 (for glucose only) (22.1 mmol · h · L^-1, 95% CI 17.7, 26.6; P = 0.01) No significant differences in glucose or insulin iAUC_net were observed in comparison of SRA3 and SIT. There was no statistically significant effect of condition on triglyceride iAUC_net.

CONCLUSIONS

In adults with medication-controlled T2D, interrupting prolonged sitting with 6-min SRAs every 60 min reduced postprandial glucose and insulin responses. Other frequencies of interruptions and potential longer-term benefits require examination to clarify clinical relevance.