The cross-sectional associations between objectively measured sedentary time and cardiometabolic health markers in adults - a systematic review with meta-analysis component

Relation of Cognitive Reserve Indicator to Heart Disease and Cardiac Structure and Function: A Large Community-Based Longitudinal Study

BACKGROUND

High cognitive reserve (CR) has been related to lower dementia risk, but its association with heart disease (HD) is unknown. We aimed to explore the relation of CR to HD and cardiac structure and function.

METHODS AND RESULTS

Within the UK Biobank, 349 907 HD-free participants were followed up. A composite CR indicator involving education/occupation attainment/television viewing time/confiding frequency/social connection frequency/variety of leisure activities was generated, and further categorized into low/moderate/high levels. Incident HD, including coronary HD, cardiac arrhythmia, and heart failure, was ascertained on the basis of medical records. During the follow-up, a subsample (n=31 182) underwent cardiac magnetic resonance imaging to assess ventricular structure and function. Data were analyzed using Cox regression, Laplace regression, and linear regression. Compared with low CR, the hazard ratio and 95% CI of any HD for high CR was 0.78 (0.75-0.80) (including 0.68 [0.66-0.71] for coronary HD, 0.91 [0.87-0.95] for cardiac arrhythmia, and 0.63 [0.58-0.68] for heart failure). Furthermore, high CR was associated with delayed HD onset by 1.59 (95% CI, 1.37-1.82) years compared with low CR. In cardiac magnetic resonance imaging data analysis, compared with low CR, high CR was associated with larger left ventricular end-diastolic volume (β, 0.13 [95% CI, 0.09-0.17]), left ventricular end-systolic volume (β, 0.05 [95% CI, 0.01-0.10]), left ventricular stroke volume (β, 0.16 [95% CI, 0.12-0.21]), and left ventricular ejection fraction (β, 0.08 [95% CI, 0.03-0.13]).

CONCLUSIONS

High CR is associated with favorable HD health. Our findings suggest that the beneficial effect of CR is not limited to dementia but also HD.

Move for Life an intervention for inactive adults aged 50 years and older: a cluster randomised feasibility trial

Background

Move for Life (MFL) is a theory-informed intervention that was developed to augment established physical activity (PA) programmes and enable inactive adults aged 50 years and older to be more active. This study examined the feasibility of MFL and sought to provide evidence of its potential for improving PA and associated health outcomes.

Methods

A 3-arm cluster randomised feasibility trial compared MFL intervention, usual provision (UP) and control (CON) groups at baseline (T0), post-intervention (T1, at 8, 10 or 12- weeks) and 6-month follow up (T2). We used purposive sampling strategies to recruit participants according to characteristics of interest. Feasibility outcomes assessed recruitment, fidelity, adherence, retention and data completion rates based on pre-set criteria. Primary outcomes were accelerometer-based moderate-to-vigorous intensity PA (MVPA) and self-reported compliance with physical activity guidelines (PAGL). Secondary outcomes included light intensity PA (LiPA), standing time, sedentary time, body composition (adiposity), physical function and psychological well-being. We used linear mixed models (continuous outcomes) or generalized estimated equations (categorical outcomes) to estimate group differences over time in the study outcomes.

Results

Progression criteria for feasibility outcomes were met, and 733 individuals were recruited. Considering a 6-month period (T0-T2), while self-reported compliance with PAGL increased in MFL relative to UP and CON and in UP relative to CON, standing time decreased in MFL relative to CON and sedentary time increased in the latter compared to UP. Waist circumference decreased in MFL relative to UP and CON. MFL outperformed UP in the Timed Up and Go Test while MFL and UP increased the distance covered in the Six-Minute Walk Test compared to CON. Psychological well-being increased in MFL relative to CON (all p < 0.05).

Conclusion

Findings show that MFL is feasible, while data are promising with regards to the potential of improving community PA programmes for adults aged 50 or more years.

Clinical trial registration

https://www.isrctn.com/Registration#ISRCTN11235176.

A multiple technology-based and individually-tailored Sit Less program for people with cardiovascular disease: A randomized controlled trial study protocol

Sedentary behavior, a key modifiable risk factor for cardiovascular disease, is prevalent among cardiovascular disease patients. However, few interventions target sedentary behavior in this group. This paper describes the protocol of a parallel two-group randomized controlled trial for a novel multi-technology sedentary behavior reduction intervention for cardiovascular disease patients (registered at Clinicaltrial.gov, NCT05534256). The pilot trial (n = 70) will test a 12-week "Sit Less" program, based on Habit Formation theory. The 35 participants in the intervention group will receive an instructional goal-setting session, a Fitbit for movement prompts, a smart water bottle (HidrateSpark) to promote hydration and encourage restroom breaks, and weekly personalized text messages. A control group of 35 will receive the American Heart Association's "Answers by Heart" fact sheets. This trial will assess the feasibility and acceptability of implementing the "Sit Less" program with cardiovascular disease patients and the program's primary efficacy in changing sedentary behavior, measured by the activPAL activity tracker. Secondary outcomes include physical activity levels, cardiometabolic biomarkers, and patient-centered outcomes (i.e. sedentary behavior self-efficacy, habit strength, and fear of movement). This study leverages commonly used mobile and wearable technologies to address sedentary behavior in cardiovascular disease patients, a high-risk group. Its findings on the feasibility, acceptability and primary efficacy of the intervention hold promise for broad dissemination.

Tiredness after work associates with less leisure-time physical activity

Physical activities and sedentary behaviors take place in different contexts. This study aimed to determine if the context, total score, and leisure-time MET-index assessed by the Baecke questionnaire associate with each other or with sedentary behavior and physical activity outcomes from a 4-week accelerometer measurement in physically inactive adults with overweight. The item "After working I am tired" correlated negatively with items related to leisure-time physical activity and sports participation. The total Baecke Score showed weak but significant correlations with accelerometer-measured sedentary behavior, physical activity, daily steps, and mean activity intensity of the day (r = - 0.33, 0.41, 0.35, and 0.41, respectively). The associations strengthened when the Sport Index was omitted from the Score. The leisure-time MET-Index did not correlate with accelerometer-measured sedentary behavior or physical activity. Tiredness after working associated with less self-reported physical activity during leisure time. This suggests that better recovery from work-related stress could increase leisure-time physical activity, or increasing leisure-time physical activity could reduce tiredness after working. Moreover, among self-reportedly inactive adults with overweight, focusing the questionnaire on work and non-sport leisure time instead of total time might give more accurate estimates of sedentary behavior and physical activity when compared to accelerometry.The study is registered at ClinicalTrials.gov (NCT03101228, 05/04/2017).

Decreasing Sedentary Behaviors in Youth to Prevent and Manage Childhood Obesity: Is It Realistic?

PURPOSE OF REVIEW

Decreasing sedentary behaviors has been proposed as one approach to reduce the rate of obesity in youth. This review summarizes the contemporary literature examining the efficacy of these interventions in the school and community along with an additional focus on the role of socioeconomic status in these interventions.

RECENT FINDINGS

Studies that focus on decreasing sedentary behavior have utilized a wide variety of strategies in a number of settings. The effects of these interventions are often hindered by non-standard outcome measures, study infidelity, and subjective measures of sedentary time. However, interventions that incorporate engaged stakeholders and include younger subjects appear to be the most likely to succeed. Promising interventions to decrease sedentary behaviors have been shown in recent clinical trials; however, replicating and sustaining these results is challenging. From the available literature, school-based interventions have the potential of reaching the largest group of children. In contrast, interventions in younger children, particularly those with invested parents, seem to be the most effective.

The effects of a 6-month intervention aimed to reduce sedentary time on skeletal muscle insulin sensitivity: a randomized controlled trial

Sedentary behavior (SB) and physical inactivity associate with impaired insulin sensitivity. We investigated whether an intervention aimed at a 1-h reduction in daily SB during 6 mo would improve insulin sensitivity in the weight-bearing thigh muscles. Forty-four sedentary inactive adults [mean age 58 (SD 7) yr; 43% men] with metabolic syndrome were randomized into intervention and control groups. The individualized behavioral intervention was supported by an interactive accelerometer and a mobile application. SB, measured with hip-worn accelerometers in 6-s intervals throughout the 6-mo intervention, decreased by 51 (95% CI 22-80) min/day and physical activity (PA) increased by 37 (95% CI 18-55) min/day in the intervention group with nonsignificant changes in these outcomes in the control group. Insulin sensitivity in the whole body and in the quadriceps femoris and hamstring muscles, measured with hyperinsulinemic-euglycemic clamp combined with [18F]fluoro-deoxy-glucose PET, did not significantly change during the intervention in either group. However, the changes in hamstring and whole body insulin sensitivity correlated inversely with the change in SB and positively with the changes in moderate-to-vigorous PA and daily steps. In conclusion, these results suggest that the more the participants were able to reduce their SB, the more their individual insulin sensitivity increased in the whole body and in the hamstring muscles but not in quadriceps femoris. However, according to our primary randomized controlled trial results, this kind of behavioral interventions targeted to reduce sedentariness may not be effective in increasing skeletal muscle and whole body insulin sensitivity in people with metabolic syndrome at the population level.NEW & NOTEWORTHY Aiming to reduce daily SB by 1 h/day had no impact on skeletal muscle insulin sensitivity in the weight-bearing thigh muscles. However, successfully reducing SB may increase insulin sensitivity in the postural hamstring muscles. This emphasizes the importance of both reducing SB and increasing moderate-to-vigorous physical activity to improve insulin sensitivity in functionally different muscles of the body and thus induce a more comprehensive change in insulin sensitivity in the whole body.

Lifestyle Patterns in Patients with Type 2 Diabetes

Modern lifestyles have led to sedentary behavior, lower participation in active movement and physical activities during leisure time, unhealthy diets, and increased exposure to stress. It is important to examine the interaction of several lifestyle risk factors instead of focusing on one alone. The purpose of this study was to identify lifestyle patterns in a group of patients with type 2 diabetes and the associations of its components with certain metabolic parameters. Using principal component analysis, we identified three dietary patterns: the prudent pattern (fat, oil, cereals, potatoes, vegetables, fish, nuts, seeds and fruits), the Western pattern (meat and meat products, eggs and soft drinks) and the traditional pattern (milk and its derivatives, soups and sauces, with a low intake of sugar/snacks). In addition, using the same method of analysis, we identified two lifestyle patterns: the inadequate lifestyle pattern (Western dietary pattern, increased hours of sleep and lower levels of stress) and the traditional lifestyle pattern (traditional dietary pattern, increased physical activity (PA) and non-smoking status). The inadequate lifestyle pattern was associated with younger age, hypertension and diabetic neuropathy. The traditional lifestyle pattern was related to lower postprandial blood glucose levels. Sedentary individuals were more likely to be over 65 years old and to have higher glycated hemoglobin (HbA1c). Smokers were also more likely to have inadequate glycemic and lipid profile control.

Paradoxical Associations of Occupational and Nonoccupational Sedentary Behavior With Cardiovascular Disease Risk Measures in Desk Workers

OBJECTIVES

We assessed sedentary behavior (SB) patterns and examined its associations, by domain, with cardiovascular disease (CVD) risk measures in desk workers ( N = 273).

METHODS

Sedentary behavior was measured by activPAL3 and partitioned into occupational and nonoccupational SB. Cardiovascular disease risk measures included blood pressure, pulse wave velocity, heart rate, and heart rate variability. Paired t tests evaluated patterns of SB across domains. Linear regressions estimated associations of occupational and nonoccupational SB with CVD risk measures.

RESULTS

Participants spent 69% of their time in SB; higher proportions were accumulated during occupational versus nonoccupational time. Higher all-domain SB was only associated with higher pulse wave velocity. Paradoxically, greater nonoccupational SB unfavorably associated with CVD risk measures, while higher occupational SB favorably correlated to CVD risk measures.

CONCLUSIONS

Observed paradoxical associations suggest that domain should be considered in efforts to improve cardiovascular health by reducing SB.

Sedentary Behaviour-A Target for the Prevention and Management of Cardiovascular Disease

Cardiovascular disease (CVD) is highly prevalent and can lead to disability and premature mortality. Sedentary behaviour, defined as a low energy expenditure while sitting or lying down, has been identified as an independent risk factor for CVD. This article discusses (1) the association of total sedentary time and patterns of accumulating sedentary time with CVD risk markers, CVD incidence and mortality; (2) acute experimental evidence regarding the acute effects of reducing and breaking up sedentary time on CVD risk markers; and (3) the effectiveness of longer-term sedentary behaviour interventions on CVD risk. Findings suggest that under rigorously controlled laboratory and free-living conditions, breaking up sedentary time improves cardiovascular risk markers in individuals who are healthy, overweight or obese, or have impaired cardiovascular health. Breaking up sedentary time with walking may have the most widespread benefits, whereas standing breaks may be less effective, especially in healthy individuals. There is also growing evidence that sedentary behaviour interventions may benefit cardiovascular risk in the longer term (i.e., weeks to months). Reducing and breaking up sedentary time may, therefore, be considered a target for preventing and managing CVD. Further research is needed to determine the effectiveness of sedentary behaviour interventions over the long-term to appropriately inform guidelines for the management of CVD.

Long sedentary time is associated with worsened cardiometabolic risk factors among university employees in Eastern Ethiopia

Sedentary time is associated with increased risks of detrimental health outcomes. Prolonged sedentary time associates with cardiometabolic risk factors and increased mortality regardless of physical activity. Therefore, the purpose of this study was to examine the associations of sedentary time and cardiometabolic risk factors among university employees in Eastern Ethiopia. A cross-sectional study was conducted among 1200 participants. Data were collected using the World Health Organization STEPS survey instrument, and sedentary behavior questionnaire in hour per day. Sedentary time is the time spent for any duration (minutes per day or hours per day) by considering a local context. Study participants were asked how many minutes or hours they spent in sedentary time at work, their leisure time and in transportation. Finally, the total sedentary time was calculated by the sum of the individual spent in sedentary time at work, leisure, and transportation. Cardiometabolic risk factors were assessed with blood samples analysis and anthropometric measurements. The associations between sedentary time and cardiometabolic risk factors were examined using linear regression models. An adjusted coefficient (β) with the 95% confidence interval (CI) was used to report the results. p value < 0.05 was considered for statistical significance. The mean age of the study participants were (35 ± 9.4 years). Almost half of the study participants, 566 (48.6) were women and 598 (51.4%) were men. As the total sedentary time was increased by one unit, the body mass index increased by β = 0.61; (95% CI 0.49-0.71),waist circumference increased by β = 1.48; (95% CI 1.14-1.82), diastolic blood pressure increased by β = 0.87; (95% CI 0.56-1.18), systolic blood pressure increased by β = 0.95; (95% CI 0.45-1.48), triglycerides increased by β = 7.07; (95% CI 4.01-10.14), total cholesterol increased by β = 3.52; (95% CI 2.02-5.02), fasting plasma glucose increased by β = 4.15; (95% CI 5.31-4.98) and low-density lipoprotein cholesterol increased by β = 2.14; (95% CI 0.96-3.33) with the effects of other variables maintain constant. These findings depict the need for strategies that policymakers should promote physical activity and encouraging the breaking up of prolonged sedentary time to reduce cardiometabolic risk factors among university employees in Ethiopia.

Joint Profiles of Sedentary Time and Physical Activity in Adults and Their Associations with Cardiometabolic Health

PURPOSE

This study aimed to identify and characterize joint profiles of sedentary time and physical activity among adults and to investigate how these profiles are associated with markers of cardiometabolic health.

METHODS

The participants included 3702 of the Northern Finland Birth Cohort 1966 at age 46 yr, who wore a hip-worn accelerometer during waking hours and provided seven consecutive days of valid data. Sedentary time, light-intensity physical activity, and moderate- to vigorous-intensity physical activity on each valid day were obtained, and a data-driven clustering approach ("KmL3D") was used to characterize distinct joint profiles of sedentary time and physical activity intensities. Participants self-reported their sleep duration and performed a submaximal step test with continuous heart rate measurement to estimate their cardiorespiratory fitness (peak heart rate). Linear regression was used to determine the association between joint profiles of sedentary time and physical activities with cardiometabolic health markers, including adiposity markers and blood lipid, glucose, and insulin levels.

RESULTS

Four distinct groups were identified: "active couch potatoes" ( n = 1173), "sedentary light movers" ( n = 1199), "sedentary exercisers" ( n = 694), and "movers" ( n = 636). Although sufficiently active, active couch potatoes had the highest daily sedentary time (>10 h) and lowest light-intensity physical activity. Compared with active couch potatoes, sedentary light movers, sedentary exercisers, and movers spent less time in sedentary by performing more physical activity at light-intensity upward and had favorable differences in their cardiometabolic health markers after accounting for potential confounders (1.1%-25.0% lower values depending on the health marker and profile).

CONCLUSIONS

After accounting for sleep duration and cardiorespiratory fitness, waking activity profiles characterized by performing more physical activity at light-intensity upward, resulting in less time spent in sedentary, were associated with better cardiometabolic health.

The Association of Sedentary Behavior and Physical Activity with Different Measurements of Metabolic Syndrome: The Jackson Heart Study

Purpose: Cross-sectional investigation of the association of sedentary behavior and physical activity with metabolic syndrome (MetS) among the African American participants in the Jackson Heart Study (JHS).

Methods: Prevalence, number of individual components, and MetS severity z-score (MetS-Z) were examined. MetS was classified using ATP-III thresholds. MetS-Z was calculated using sex-, race-, and ethnicity-specific formulas. Sedentary behavior and physical activity were calculated from the JHS Physical Activity Cohort survey (JPAC). Associations between sedentary behavior and physical activity with MetS were assessed by logistic, negative binomial, and ordinary least squares regressions.

Results: The mean participant age ( N = 3370) was 61.7 ± 11.9 years and most were female (63.9%). Among all participants, 60.5% were classified with MetS. Overall MetS-Z was moderately high (.31 ± 1.07). Most waking hours were sedentary, with just under 40 daily minutes of self-reported physical activity. Physical activity was associated with lower prevalence of MetS, the number of individual components, and MetS-Z score ( p < .05). Sedentary behavior was not associated with MetS in any fully adjusted models ( p > .05).

Conclusions: Physical activity was associated with lower cardiometabolic risk, irrespective of sedentary behavior. Further studies are needed to better understand why no relation was found between sedentary behavior and cardiometabolic risk in this cohort of African American adults.

Patterns of Accelerometer-Measured Physical Activity and Health Outcomes in Adults: A Systematic Review

PURPOSE

The aim of this study was to systematically review the literature on accelerometer-measured physical activity and health outcomes in adults.

METHODS

Eight electronic databases were searched for relevant articles published up to March 2021. Only population-based studies of adults (age ≥18 yr) that directly compared two or more categories of physical activity (i.e., bout duration, intensity, and daily/weekly frequency) with a health outcome (e.g., mortality, cardiometabolic, healthy aging, depression, sleep, and brain structure) were included.

RESULTS

Of the 15,923 publications retrieved, 52 articles were included. Twenty-eight studies directly compared the associations between physical activity accumulated in different bout durations, 31 studies directly compared the associations between physical activity accumulated in different intensities, and 9 studies directly compared the associations between the effects of varying daily and weekly frequencies of physical activity, with health outcomes. Most showed no differences in relationships with health outcomes when physical activity was accumulated in short (<10-min) or long (≥10-min) bouts. Overall, there were no differences in the relationships with most health outcomes when different intensities and daily/weekly frequencies were compared. However, in most studies, researchers did not adjust their analyses for total volume of physical activity. Moreover, variations in researcher-driven decisions about data collection and processing methods made it difficult to compare study findings.

CONCLUSIONS

These findings suggest that physical activity accumulated in many patterns of bout duration, intensity, or daily/weekly frequency is associated with a range of beneficial health outcomes in adults. Lack of adjustment for total volume of physical activity in most studies and inconsistent methods for defining components of physical activity prevent firm conclusions about which specific patterns of bout duration, intensity, and daily/weekly frequency are most important for health benefits.

The association between sedentary behaviour, physical activity and type 2 diabetes markers: A systematic review of mixed analytic approaches

The negative effect of sedentary behaviour on type 2 diabetes markers is established, but the interaction with measures of physical activity is still largely unknown. Previous studies have analysed associations with single-activity models, which ignore the interaction with other behaviours. By including results from various analytical approaches, this review critically summarises the effects of sedentary behaviour on diabetes markers and the benefits of substitutions and compositions of physical activity. Ovid Medline, Embase and Cochrane Library databases were systematically searched. Studies were selected if sedentary behaviour and physical activity were measured by accelerometer in the general population, and if associations were reported with glucose, insulin, HOMA-IR, insulin sensitivity, HbA1c, diabetes incidence, CRP and IL-6. Forty-five studies were included in the review. Conclusive detrimental associations with sedentary behaviour were determined for 2-h insulin (6/12 studies found associations), fasting insulin (15/19 studies), insulin sensitivity (4/6 studies), diabetes (3/4 studies) and IL-6 (2/3 studies). Reallocating sedentary behaviour to light or moderate-to-vigorous activity has a beneficial effect for 2-h glucose (1/1 studies), fasting insulin (3/3 studies), HOMA-IR (1/1 studies) and insulin sensitivity (1/1 studies). Compositional measures of sedentary behaviour were found to affect 2-h glucose (1/1 studies), fasting insulin (2/3 studies), 2-h insulin (1/1 studies), HOMA-IR (2/2 studies) and CRP (1/1 studies). Different analytical methods produced conflicting results for fasting glucose, 2-h glucose, 2-h insulin, insulin sensitivity, HOMA-IR, diabetes, hbA1c, CRP and IL-6. Studies analysing data by quartiles report independent associations between sedentary behaviour and fasting insulin, HOMA-IR and diabetes only for high duration of sedentary time (7-9 hours/day). However, this review could not provide sufficient evidence for a time-specific cut-off of sedentary behaviour for diabetes biomarkers. While substituting sedentary behaviour with moderate-to-vigorous activity brings greater improvements for health, light activity also benefits metabolic health. Future research should elucidate the effects of substituting and combining different activity durations and modalities.

Physical activity intensity profiles associated with cardiometabolic risk in middle-aged to older men and women

Accelerometers provide detailed data about physical activity (PA) across the full intensity spectrum. However, when examining associations with health, results are often aggregated to only a few summary measures [e.g. time spent "sedentary" or "moderate-to-vigorous" intensity PA]. Using multivariate pattern analysis, which can handle collinear exposure variables, we examined associations between the full PA intensity spectrum and cardiometabolic risk (CMR) in a population-based sample of middle-aged to older adults. Participants (n = 3660; mean ± SD age = 69 ± 8y and BMI = 26.7 ± 4.2 kg/m²; 55% female) from the EPIC-Norfolk study (UK) with valid accelerometry (ActiGraph-GT1M) data were included. We used multivariate pattern analysis with partial least squares regression to examine cross-sectional multivariate associations (r) across the full PA intensity spectrum [minutes/day at 0-5000 counts-per-minute (cpm); 5 s epoch] with a continuous CMR score (reflecting waist, blood pressure, lipid, and glucose metabolism). Models were sex-stratified and adjusted for potential confounders. There was a positive (detrimental) association between PA and CMR at 0-12 cpm (maximally-adjusted r = 0.08 (95%CI 0.06-0.10). PA was negatively (favourably) associated with CMR at all intensities above 13 cpm ranging between r = -0.09 (0.07-0.12) at 800-999 cpm and r = -0.14 (0.11-0.16) at 75-99 and 4000-4999 cpm. The strongest favourable associations were from 50 to 800 cpm (r = 0.10-0.12) in men, but from ≥2500 cpm (r = 0.18-0.20) in women; with higher proportions of model explained variance for women (R² = 7.4% vs. 2.3%). Most of the PA intensity spectrum was beneficially associated with CMR in middle-aged to older adults, even at intensities lower than what has traditionally been considered "sedentary" or "light-intensity" activity. This supports encouragement of PA at almost any intensity in this age-group.

Effects of combined training on metabolic profile, lung function, stress and quality of life in sedentary adults: A study protocol for a randomized controlled trial

Background

Both physical inactivity and sedentary behavior are considered modifiable risk factors for chronic diseases and all-cause mortality. Adult office-workers spend most of their working day in sedentary behaviors, so they are particularly at high risk of developed chronic diseases (e.g., cardiovascular diseases, metabolic disorders like diabetes mellitus, …). It seems important to promote behavioral changes that could prevent or delay metabolic disease development. Evidence supports the use of exercise programs, however, to date there are several knowledge gaps and inconsistencies in the literature regarding the effects of Combined Training (i.e., aerobic plus resistance training) in sedentary healthy adults. This paper outlines an RCT designed to evaluate the effects of a 16-week combined training program on biochemical and immune markers of metabolic disease, lung function, salivary stress hormones and subjective quality of life (primary outcomes), as well as on body composition and physical fitness (secondary outcomes) in sedentary middle-aged office-workers. Furthermore, we aimed to assess the associations between the changes promoted by the exercise program and the different variables studied.

Methods and design

This is a single-blinded two-arm RCT with parallel groups. A minimum of healthy 40 office-workers aged 40–64 years will be recruited to engage in a 16-week intervention study. After baseline assessments, participants will be randomized to one of the two groups: (1) combined training group or (2) control group. Baseline assessments will be repeated after 8 weeks of intervention (mid-testing) and upon completion of the intervention (post-testing).

Discussion

This RCT involves a multi-disciplinary approach and seems to be a relevant contribution to understanding the potential role of combined training in improving the metabolic profile, lung function, stress, and quality of life in adults. The results can provide important insights for clinical recommendations and for the optimization of strategies to prevent metabolic disorders in adults with sedentary jobs.

Trial registration

This trial is registered with ClinicalTrials.gov (registration number: NCT04868240; date of registration April 30, 2021).

Impact of BMI, Physical Activity, and Sitting Time Levels on Health-Related Outcomes in a Group of Overweight and Obese Adults with and without Type 2 Diabetes

Physical activity level and sedentary behaviors affect health status in people with obesity and type 2 diabetes (DM2); their assessment is mandatory to properly prescribe exercise programs. From January 2011 to February 2014, 293 overweight/obese adults (165 women and 128 men, mean age of 51.9 ± 9.5 years and 54.6 ± 8.3 years, respectively), with and without DM2, participated in a three-month intensive exercise program. Before starting, participants were allocated into three subgroups (overweight, body mass index or BMI = 25-29.9; class 1 of obesity, BMI = 30-34.4; or class 2 (or superior) of obesity, BMI > 35). The international physical activity questionnaire (IPAQ-it) was used to evaluate participants' baseline sitting time (SIT) and physical activity level (PAL). Stratified multiple analyses were performed using four subgroups of SIT level according to Ekelund et al., 2016 (low, 8 h/day of SIT) and three subgroups for PAL (high, moderate, and low). Health-related measures such as anthropometric variables, body composition, hematic parameters, blood pressure values, and functional capacities were studied at the beginning and at the end of the training period. An overall improvement of PAL was observed in the entire sample following the three-month intensive exercise program together with a general improvement in several health-related measures. The BMI group factor influenced the VO₂ max variations, leg press values, triglycerides, and anthropometric variables, while the SIT group factor impacted the sitting time, VO₂ max, glycemic profile, and fat mass. In this study, baseline PAL and SIT did not seem to influence the effects of an exercise intervention. The characteristics of our educational program, which also included a physical exercise protocol, allowed us to obtain positive results.

Physical activity in management of persons with obesity

Physical activity and exercise have many benefits in persons with obesity, helping with weight loss, body fat loss, abdominal visceral fat loss and possibly with weight maintenance after weight loss. The effect of exercise training (endurance or endurance plus resistance or high-intensity interval training) alone on weight loss as outcome appears relatively modest, amounting to only a few kg. However, endurance training during weight loss has been shown to increase V̇O₂max and resistance training during weight loss leads to lower loss in lean body mass and increased muscle strength. In addition, higher physical activity levels improve cardiovascular risk, whatever weight variations. Specifically, physical activity or exercise is part of lifestyle measures for prevention of type 2 diabetes and substantially helps with metabolic control in patients with type 2 diabetes. The importance of physical activity counselling and exercise prescription in the management strategy will depend on specific treatment objectives as defined for a given patient, including weight loss, prevention of weigh regain, prevention of cardio-metabolic comorbidities, lean body mass preservation but also improvement in quality of life or development of social links. The 5 A's strategy consisting in: Ask, Assess, Advise, Agree, Assist (or Arrange) appears well adapted in this setting. Professionals need to be aware of the many barriers patients with obesity may meet on their way to increase habitual physical activity as specific solutions should be proposed. A major challenge is how to improve adherence to new physical activity habits over time.

The Impact of a 12-Month Activity Tracker Intervention on Activity Behavior Across Body Mass Index Subgroups Among Recent Retirees: Post Hoc Analysis of a Randomized Controlled Trial

BACKGROUND

This study examined the effectiveness of a 12-month activity tracker-based intervention on activity behavior among recent retirees (Enhancing physical ACTivity and healthy aging among recent REtirees [REACT]) in subgroups based on body mass index.

METHODS

REACT trial randomized 231 participants (mean age 65.2) into intervention and control groups. Main outcomes were accelerometer-measured moderate-to-vigorous (MVPA) and light physical activity (LPA) and sedentary time (SED) measured at baseline and 3-, 6-, and 12-month follow-ups. As a post hoc analysis, the intervention effect was examined among participants with normal weight (n = 77), overweight (n = 89), and obesity (n = 61).

RESULTS

An intervention effect was observed among participants with obesity in LPA (time × group P = .045) mirrored by a similar, albeit nonsignificant, effect in SED (P = .067), but not in MVPA (P = .92). A transient increase of 41 minutes per day (95% confidence interval, 14 to 68) in LPA was observed at 6 months among the intervention group, with a concomitant decrease of 42 minutes per day (-72 to -12) in SED. However, these changes were not maintained at 12 months. No between-group differences in changes over time were observed among participants with normal or overweight.

CONCLUSIONS

Activity trackers may be particularly suitable for promoting changes in LPA and SED among older adults with obesity. However, their long-term effectiveness might be limited.

Application of Convolutional Neural Network Algorithms for Advancing Sedentary and Activity Bout Classification

Background

Machine learning has been used for classification of physical behavior bouts from hip-worn accelerometers; however, this research has been limited due to the challenges of directly observing and coding human behavior "in the wild." Deep learning algorithms, such as convolutional neural networks (CNNs), may offer better representation of data than other machine learning algorithms without the need for engineered features and may be better suited to dealing with free-living data. The purpose of this study was to develop a modeling pipeline for evaluation of a CNN model on a free-living data set and compare CNN inputs and results with the commonly used machine learning random forest and logistic regression algorithms.

Method

Twenty-eight free-living women wore an ActiGraph GT3X+accelerometer on their right hip for 7 days. A concurrently worn thigh-mounted activPAL device captured ground truth activity labels. The authors evaluated logistic regression, random forest, and CNN models for classifying sitting, standing, and stepping bouts. The authors also assessed the benefit of performing feature engineering for this task.

Results

The CNN classifier performed best (average balanced accuracy for bout classification of sitting, standing, and stepping was 84%) compared with the other methods (56% for logistic regression and 76% for random forest), even without performing any feature engineering.

Conclusion

Using the recent advancements in deep neural networks, the authors showed that a CNN model can outperform other methods even without feature engineering. This has important implications for both the model's ability to deal with the complexity of free-living data and its potential transferability to new populations.

Socioeconomic correlates of sedentary time during pregnancy among women at risk of gestational diabetes in the UK

Little is known about the relationship between socioeconomic position (SEP) and duration and patterning of objectively measured sedentary time (ST) among adults, especially adults at high risk of diabetes. The aim of this study was to examine cross-sectional associations of SEP with ST (total, prolonged ST, breaks in ST) and self-reported TV time among pregnant women at risk of gestational diabetes in the UK. At 20 weeks' gestation, pregnant women (n=174) wore an activPAL accelerometer and reported their usual TV time. Generalized linear mixed models were used to test associations of education, household income and area-level deprivation (separately and with mutual adjustment) with total ST, prolonged ST and breaks in ST. Logistic regression models were used to test associations between SEP indicators and high (≥2h/day) TV time. Those with the lowest education, lowest household income and highest area-level deprivation had the lowest ST and lowest prolonged ST. After mutual adjustment, area-level deprivation remained associated with total ST (β=0.10 [0.01, 0.20]). There was an inverse association between area-level deprivation and breaks in sedentary time (exp(b)=1.11 [1.01, 1.22]). Education was the only SEP correlate of high TV time, with more of those with least education reporting high TV time; this association persisted after adjustment for household income and area-level deprivation. The association between SEP and total and prolonged ST (positive) was the opposite of the association between education and high TV time (negative) in this sample of high-risk pregnant women. These findings should inform interventions to reduce sedentary time.

Effect of Underlying Cardiometabolic Diseases on the Association Between Sedentary Time and All-Cause Mortality in a Large Japanese Population: A Cohort Analysis Based on the J-MICC Study

Background This study aimed to determine the association between sedentary time and mortality with regard to leisure-time physical activity with or without cardiometabolic diseases such as hypertension, dyslipidemia, and diabetes mellitus. Methods and Results Using data from the J-MICC (Japan Multi-Institutional Collaborative Cohort) Study, 64 456 participants (29 022 men, 35 434 women) were analyzed. Hazard ratios (HRs) and 95% CIs were used to characterize the relative risk of all-cause mortality to evaluate its association with sedentary time (categorical variables: <5, 5 to <7, 7 to <9, ≥9 h/d and 2-hour increments in exposure) according to the self-reported hypertension, dyslipidemia, and diabetes mellitus using a Cox proportional hazards model. A total of 2257 participants died during 7.7 years of follow-up. The corresponding HRs for each 2-hour increment in sedentary time among participants with all factors, no factors, hypertension, dyslipidemia, and diabetes mellitus were 1.153 (95% CI, 1.114-1.194), 1.125 (95% CI, 1.074-1.179), 1.202 (95% CI, 1.129-1.279), 1.176 (95% CI, 1.087-1.273), and 1.272 (95% CI, 1.159-1.396), respectively. Furthermore, when analyzed according to the combined different factors (hypertension, dyslipidemia, and diabetes mellitus), HRs increased with each additional factor, and participants reporting all 3 conditions had the highest HR of 1.417 (95% CI, 1.162-1.728) independently of leisure-time metabolic equivalents. Conclusions The association between sedentary time and increased mortality is stronger among patients with hypertension, dyslipidemia, and diabetes mellitus regardless of leisure-time physical activity in a large Japanese population.

The Influence of Sitting, Standing, and Stepping Bouts on Cardiometabolic Health Markers in Older Adults

Aside from total time spent in physical activity behaviors, how time is accumulated is important for health. This study examined associations between sitting, standing, and stepping bouts, with cardiometabolic health markers in older adults. Participants from the Mitchelstown Cohort Rescreen Study (N = 221) provided cross-sectional data on activity behaviors (assessed via an activPAL3 Micro) and cardiometabolic health. Bouts of ≥10-, ≥30-, and ≥60-min sitting, standing, and stepping were calculated. Linear regression models were fitted to examine the associations between bouts and cardiometabolic health markers. Sitting (≥10, ≥30, and ≥60 min) and standing (≥10 and ≥30 min) bouts were detrimentally associated with body composition measures, lipid markers, and fasting glucose. The effect for time spent in ≥60-min sitting and ≥30-min standing bouts was larger than shorter bouts. Fragmenting sitting with bouts of stepping may be targeted to benefit cardiometabolic health. Further insights for the role of standing need to be elicited.

Accumulation patterns of sedentary time and breaks and their association with cardiometabolic health markers in adults

Breaking up sedentary time with physical activity (PA) could modify the detrimental cardiometabolic health effects of sedentary time. Our aim was to identify profiles according to distinct accumulation patterns of sedentary time and breaks in adults, and to investigate how these profiles are associated with cardiometabolic outcomes. Participants (n = 4439) of the Northern Finland Birth Cohort 1966 at age 46 years wore a hip-worn accelerometer for 7 consecutive days during waking hours. Uninterrupted ≥1-min sedentary bouts were identified, and non-sedentary bouts in between two consecutive sedentary bouts were considered as sedentary breaks. K-means clustering was performed with 65 variables characterizing how sedentary time was accumulated and interrupted. Linear regression was used to determine the association of accumulation patterns with cardiometabolic health markers. Four distinct groups were formed as follows: "Couch potatoes" (n = 1222), "Prolonged sitters" (n = 1179), "Shortened sitters" (n = 1529), and "Breakers" (n = 509). Couch potatoes had the highest level of sedentariness and the shortest sedentary breaks. Prolonged sitters, accumulating sedentary time in bouts of ≥15-30 min, had no differences in cardiometabolic outcomes compared with Couch potatoes. Shortened sitters accumulated sedentary time in bouts lasting <15 min and performed more light-intensity PA in their sedentary breaks, and Breakers performed more light-intensity and moderate-to-vigorous PA. These latter two profiles had lower levels of adiposity, blood lipids, and insulin sensitivity, compared with Couch potatoes (1.1-25.0% lower values depending on the cardiometabolic health outcome, group, and adjustments for potential confounders). Avoiding uninterrupted sedentary time with any active behavior from light-intensity upwards could be beneficial for cardiometabolic health in adults.

Objectively Measured Sedentary Time Before and After Transition to Retirement: The Finnish Retirement and Aging Study

BACKGROUND

Retirement is associated with an increase in self-reported daily sedentary time, but no longitudinal evidence exists on how objectively measured sedentary time changes during retirement transition. The aim of this study was to compare objectively measured daily and hourly sedentary time before and after retirement and examine whether these changes differ by gender and occupational status.

METHODS

The study population consisted of 478 participants (mean age 63.2 years, standard deviation 1.7, 85% women) from the Finnish Retirement and Aging Study. Sedentary time was measured using a wrist-worn triaxial ActiGraph accelerometer before and after transition to retirement with 1 year interval. Preretirement occupational status was categorized as manual and non-manual.

RESULTS

Daily sedentary time was 8 hours 10 minutes in women and 9 hours 49 minutes in men before retirement. Considering all measurement days before and after retirement, daily sedentary time increased in women by 29 minutes (95% confidence interval [CI]: 20 to 38). Especially women retiring from manual occupations showed marked increase in sedentary time (63 minutes, 95% CI: 50 to 77). When only non-working days before retirement were considered, increase in daily sedentary time among women was less marked (16 minutes, 95% CI: 7 to 25). Among men, daily sedentary time did not change in retirement transition (-7 minutes, 95% CI: -26 to 12).

CONCLUSIONS

Objectively measured sedentary time increases among women and remains at high level among men during the retirement transition. Attention should be paid to reduce daily sedentary time in retiring women and men.

Cross-sectional associations of device-measured sedentary behaviour and physical activity with cardio-metabolic health in the 1970 British Cohort Study

AIMS

This study aimed to examine the cross-sectional associations of thigh accelerometry-assessed sedentary behaviour and moderate-to-vigorous physical activity (MVPA) with cardio-metabolic health markers and prevalent diabetes in a population sample of middle-aged British adults.

METHODS

Participants (n = 4892) from the age-46-to-48 wave of the 1970 British Cohort Study were fitted with a waterproofed activPAL3 micro device. Total/prolonged sedentary time, breaks and MVPA were the main exposures. We dichotomized prolonged sedentary time and MVPA based on the corresponding median, generating four combinations as categorical exposures. Outcomes comprised of diabetes and seven cardio-metabolic health markers. We used logistic regression and generalized linear models to examine independent/joint associations, conducting a minimally adjusted model including demographics and contextual covariates, and further adjusted for total sedentary time and/or MVPA as applicable.

RESULTS

Each set of 10 sedentary breaks and 1 h of prolonged sedentary time were associated with HbA_1c (mmol/mol) [B = -0.18 (-0.33, -0.03) and 2.35 (1.01, 3.69), respectively]. Each set of 10 sedentary breaks and 1 h of MVPA were favourably associated with diabetes [adjusted odds ratio (AOR): 0.80 (0.71, 0.99) and 0.42 (0.26, 0.67), respectively]. Joint analyses showed that only the low MVPA × long sedentary time combination had significantly higher odds for diabetes than the referent high MVPA × short sedentary time combination [AOR: 1.89 (1.17, 3.03)].

CONCLUSIONS

Each set of additional 10 sedentary breaks per day was associated with 20% lower odds for diabetes. A low physical activity level combined with long sedentary time might synergistically deteriorate cardio-metabolic health.

The Influence of Different Physical Activity Behaviours on the Gut Microbiota of Older Irish Adults

OBJECTIVE

A 24-hour day is made up of time spent in a range of physical activity (PA) behaviours, including sleep, sedentary time, standing, light-intensity PA (LIPA) and moderate-to-vigorous PA (MVPA), all of which may have the potential to alter an individual's health through various different pathways and mechanisms. This study aimed to explore the relationship between PA behaviours and the gut microbiome in older adults.

DESIGN

Cross-sectional study.

SETTINGS AND PARTICIPANTS

Participants (n=100; age 69.0 [3.0] years; 44% female) from the Mitchelstown Cohort Rescreen (MCR) Study (2015-2017).

METHODS

Participants provided measures of gut microbiome composition (profiled by sequencing 16S rRNA gene amplicons), and objective measures of PA behaviours (by a 7-day wear protocol using an activPAL3 Micro).

RESULTS

Standing time was positively correlated with the abundance of butyrate-producing and anti-inflammatory bacteria, including Ruminococcaceae, Lachnospiraceae and Bifidobacterium, MVPA was positively associated with the abundance of Lachnospiraceae bacteria, while sedentary time was associated with lower abundance of Ruminococcaceae and higher abundance of Streptococcus spp.

CONCLUSION

Physical activity behaviours appear to influence gut microbiota composition in older adults, with different PA behaviours having diverging effects on gut microbiota composition.

Both sedentary time and physical activity are associated with cardiometabolic health in overweight adults in a 1 month accelerometer measurement

The aim of this study was to examine the associations of cardiometabolic health markers with device-measured sedentary behavior (SB) duration and different intensities of physical activity (PA) among overweight working-aged adults with low self-reported PA levels. This cross-sectional analysis included 144 subjects (42 men) with mean age of 57 (SD 6.5) years and mean BMI of 31.7 (SD 4) kg/m². SB and standing time, breaks in sedentary time, light PA (LPA) and moderate-to-vigorous PA (MVPA) were measured for 4 consecutive weeks (mean 25 days, SD 4) with hip-worn accelerometers. Fasting plasma glucose, insulin, HbA_1c, triglycerides and total cholesterol, HDL and LDL were measured from venous blood samples. HOMA-IR index was calculated as a surrogate of insulin resistance. The associations were examined using linear models. LPA, MVPA, and daily steps associated with better insulin sensitivity and favorable plasma lipid profile, when adjusted for age, sex and BMI, whereas greater proportion of SB associated with insulin resistance and unfavorable lipid profile. As all PA intensities associated with better cardiometabolic health, the total daily duration of PA may be more relevant than intensity in maintaining metabolic health in overweight adults, if the current guidelines for PA are not met.

Trial Registration: ClinicalTrials.gov NCT03101228, registered 05/04/2017, https://clinicaltrials.gov/show/NCT03101228.

Objectively Measured Sedentary Behavior and Physical Fitness in Adults: A Systematic Review and Meta-Analysis

Background: Sedentary behavior has been considered an independent risk factor to health. The aim of this systematic review and meta-analysis was to examine associations between objectively measured sedentary time and physical fitness components in healthy adults. Methods: Four electronic databases (Web of Science, Scopus, Pubmed and Sport Discus) were searched (up to 20 September 2020) to retrieve studies on healthy adults which used observational, cohort and cross-sectional designs. Studies were included if sedentary time was measured objectively and examined associations with the health- or skill-related attributes of physical fitness (e.g., muscular strength, cardiorespiratory fitness, balance). After applying additional search criteria, 21 papers (11,101 participants) were selected from an initial pool of 5192 identified papers. Results: Significant negative associations were found between total sedentary time with cardiorespiratory fitness (r = −0.164, 95%CI: −0.240, −0.086, p < 0.001), muscular strength (r = −0.147, 95%CI: −0.266, −0.024, p = 0.020) and balance (r = −0.133, 95%CI: −0.255, −0.006, p = 0.040). Conclusions: The evidence found suggests that sedentary time can be associated with poor physical fitness in adults (i.e., muscular strength, cardiorespiratory fitness and balance), so strategies should be created to encourage behavioral changes.

Comparison of Sedentary Time Between Thigh-Worn and Wrist-Worn Accelerometers

Background: The accuracy of wrist-worn accelerometers in identifying sedentary time has been scarcely studied in free-living conditions. The aim of this study was to compare daily sedentary time estimates between a thigh-worn accelerometer, which measured sitting and lying postures, and a wrist-worn accelerometer, which measured low levels of movement. Methods: The study population consisted of 259 participants (Mage = 62.8 years, SD = 0.9) from the Finnish Retirement and Aging Study (FIREA). Participants wore an Axivity AX3 accelerometer on their mid-thigh and an Actigraph wActiSleep-BT accelerometer on their non-dominant wrist simultaneously for a minimum of 4 days in free-living conditions. Two definitions to estimate daily sedentary time were used for data from the wrist-worn accelerometer: 1) the count cutpoint, ≤1853 counts per minute; and 2) the Euclidean Norm Minus One (ENMO) cutpoint, <30 mg. Results: Compared to the thigh-worn accelerometer, daily sedentary time estimate was 63 min (95% confidence interval [CI] = −53 to −73) lower by the count cutpoint and 50 min (95% CI = 34 to 67) lower by the ENMO cutpoint. The limits of agreement in daily sedentary time estimates between the thigh- and cutpoint methods for wrist-worn accelerometers were wide (the count cutpoint: −117 to 243, the ENMO cutpoint: −212 to 313 min). Conclusions: Currently established cutpoint-based methods to estimate sedentary time from wrist-worn accelerometers result in underestimation of daily sedentary time compared to posture-based estimates of thigh-worn accelerometers. Thus, sedentary time estimates obtained from wrist-worn accelerometers using currently available cutpoint-based methods should be interpreted with caution and future work is needed to improve their accuracy.

The physical activity at work (PAW) study protocol: a cluster randomised trial of a multicomponent short-break intervention to reduce sitting time and increase physical activity among office workers in Thailand

BACKGROUND

High levels of sedentary behaviour (SB) are associated with non-communicable diseases. In 2016, the estimated total healthcare expenditure from physical activity (PA) in Thailand added up to $190 million in international dollars. The challenge to reduce SB and increase PA among office workers is more urgent now than ever as Thailand is transforming itself from a predominantly rural country to an increasingly urban one. This study will investigate the effectiveness of a multicomponent short break intervention on the reduction of SB during office hours.

METHODS/DESIGN

This two-armed Physical Activity at Work (PAW) cluster randomised controlled trial will recruit 360 office workers from 18 offices in the Thailand's Ministry of Public Health (MOPH). Offices will be randomised to either the intervention group or the control group. The multicomponent intervention is informed by the Social Ecological Model and Behaviour Change Techniques (BCTs) and contains four components: (i) organisational, including heads of the participating divisions leading exercises, sending encouragement text messages and acknowledging efforts; (ii) social, including team movement breaks and team-based incentives; (iii) environmental, including posters to encourage exercise; and (iv) individual components including real-time PA feedback via an individual device. The main intervention component will be a short break intervention. The primary outcome of this study is the sedentary time of office workers. Secondary outcomes include time spent on PA, cardiometabolic outcomes, work productivity, musculoskeletal pain, and quality of life. The study also includes process and economic evaluations from the individual and societal perspective.

DISCUSSION

The study will be the first experimental study in Thailand to investigate the effect of a short-break intervention at the workplace on SBs of office workers and health outcomes. The study will also include a cost-effectiveness analysis to inform investments on short break interventions under the Universal Healthcare Coverage in Thailand, which includes health promotion and disease prevention component.

TRIAL REGISTRATION

The PAW study has been registered at the Thai Clinical Trials Registry (TCTR) under the study ID TCTR20200604007 . Registered 02 June 2020,.

Use of Compositional Data Analysis to Show Estimated Changes in Cardiometabolic Health by Reallocating Time to Light-Intensity Physical Activity in Older Adults

BACKGROUND

All physical activity (PA) behaviours undertaken over the day, including sleep, sedentary time, standing time, light-intensity PA (LIPA) and moderate-to-vigorous PA (MVPA) have the potential to influence cardiometabolic health. Since these behaviours are mutually exclusive, standard statistical approaches are unable to account for the impact on time spent in other behaviours.

OBJECTIVE

By employing a compositional data analysis (CoDA) approach, this study examined the associations of objectively measured time spent in sleep, sedentary time, standing time, LIPA and MVPA over a 24-h day on markers of cardiometabolic health in older adults.

METHODS

Participants (n =366; 64.6 years [5.3]; 46% female) from the Mitchelstown Cohort Rescreen Study provided measures of body composition, blood lipid and markers of glucose control. An activPAL3 Micro was used to obtain objective measures of sleep, sedentary time, standing time, LIPA and MVPA, using a 7-day continuous wear protocol. Regression analysis, using geometric means derived from CoDA (based on isometric log-ratio transformed data), was used to examine the relationship between the aforementioned behaviours and markers of cardiometabolic health.

RESULTS

Standing time and LIPA showed diverging associations with markers of body composition. Body mass index (BMI), body mass and fat mass were negatively associated with LIPA (all p <0.05) and positively associated with standing time (all p <0.05). Sedentary time was also associated with higher BMI (p <0.05). No associations between blood markers and any PA behaviours were observed, except for triglycerides, which were negatively associated with standing time (p < 0.05). Reallocating 30 min from sleep, sedentary time or standing time, to LIPA, was associated with significant decreases in BMI, body fat and fat mass.

CONCLUSION

This is the first study to employ CoDA in older adults that has accounted for sleep, sedentary time, standing time, LIPA and MVPA in a 24-h cycle. The findings support engagement in LIPA to improve body composition in older adults. Increased standing time was associated with higher levels of adiposity, with increased LIPA associated with reduced adiposity; therefore, these findings indicate that replacing standing time with LIPA is a strategy to lower adiposity.

Relationship Between Pain and Sedentary Behavior in Rheumatoid Arthritis Patients: A Cross-Sectional Study

OBJECTIVE

Despite the known benefits of physical activity, high numbers of individuals with rheumatoid arthritis (RA) remain physically inactive and sedentary. Little is known about the determinants of sedentary behavior (SB) in RA. This cross-sectional study was undertaken to examine a range of pain characteristics and RA-related symptoms and their relationship with objectively measured SB.

METHODS

In total, 76 adults with RA wore an activPAL4 accelerometer (PAL Technologies) over a 7-day period. Pain characteristics (pain intensity, painful joint count, nonarticular pain), fatigue, sleep, depression, anxiety, and disease activity were assessed. Analyses were first conducted to evaluate correlations with sedentary time. The independent contribution of pain characteristics to variation in SB was analyzed with multivariable linear regression (adjusted for demographic data and disease activity).

RESULTS

Participants with valid accelerometer data (n = 72) spent a mean ± SD of 533.7 ± 100.1 minutes/day in SB. Positive associations with daily SB were found for pain intensity (r = 0.31, P < 0.01) and number of painful joints (r = 0.24, P < 0.05) but not nonarticular pain. In multivariable analyses, pain characteristics were not independently associated with SB. Analyses indicated that disease activity had an indirect association with SB mediated by pain intensity. Other correlates of daily SB included anxiety and depression but not fatigue or sleep.

CONCLUSION

Results suggest that while pain and other RA-related factors do play a role in SB, they do not appear to have a significant influence after accounting for other variables. Future research should investigate SB and the role of factors unrelated to the symptoms of RA.

Sedentary Time is Associated with Cardiometabolic Diseases in A Large Japanese Population: A Cross-Sectional Study

Aim: Accumulating evidence reveals that sedentary behavior is associated with mortality and cardiometabolic disease; however, there are potential age and sex differences in sedentary behavior and health outcomes that have not been adequately addressed. This study aimed to determine the association of sedentary behavior with cardiometabolic diseases such as hypertension, dyslipidemia, diabetes mellitus, and its risk factors in a large Japanese population according to age and sex.

Methods: Using data from the Japan Multi-Institutional Collaborative Cohort Study obtained from baseline surveys, data of 62,754 participants (27,930 males, 34,824 females) were analyzed. This study uses a cross-sectional design and self-administered questionnaires to evaluate sedentary time and anamnesis. For the logistic regression analysis, sedentary time < 5 h/day was used as the reference and then adjusted for age, research areas, leisure-time metabolic equivalents, and alcohol and smoking status. From the analysis of anthropometric and blood examinations, 35,973 participants (17,109 males, 18,864 females) were analyzed.

Results: For hypertension and diabetes, sedentary time was associated with a significantly higher proportion of male participants. Both sexes were associated with a significantly higher proportion of participants with dyslipidemia. Participants who had longer sedentary time tended to have increased levels of blood pressure, triglycerides, and non-high-density lipoprotein cholesterol (HDL-C), and decreased levels of HDL-C, especially in the 60–69 years group.

Conclusions: Independent of leisure-time physical activity, sedentary time was associated with cardiometabolic diseases in a large Japanese population classified by age and sex. Our findings indicate that regularly interrupting and replacing sedentary time may contribute to better physical health-related quality of life.

Exercise-Released Myokines in the Control of Energy Metabolism

Physical activity reduces cardiometabolic risk, while physical inactivity increases chronic diseases risk. This led to the idea that exercise-induced muscle contraction contributes to metabolic regulation and health. It is now well established that skeletal muscle, through the release of endocrine factors, i.e., so-called myokines, crosstalk with metabolic organs such as adipose tissue, liver and pancreas. Recent advances suggested that a number of myokines are able to modulate adipose tissue metabolism and thermogenic activity, liver endogenous glucose production and β-cell insulin secretion. This novel paradigm offers a compelling hypothesis and molecular basis to explain the link between physical inactivity and chronic diseases. Herein, we review major findings and recent advances linking exercise, myokines secretion and inter-organ crosstalk. Identifying the molecular mediators linking physical activity to metabolic health could open the path toward novel therapeutic targets in metabolic diseases.

Meta-analysis of the Relation of Television-Viewing Time and Cardiovascular Disease

To determine whether television (TV) viewing is associated with cardiovascular disease (CVD) risk, we performed a meta-analysis of currently available prospective cohort studies. We systematically searched PubMed and Web of Science through April 2019. Eligible for inclusion in the present meta-analysis was a prospective cohort study investigating the association of TV viewing time with CVD risk (CVD prevalence, CVD incidence, cardiovascular events, and cardiovascular mortality). From each study, adjusted hazard ratios (HRs) of CVD risk were extracted. We separately combined study-specific estimates for dichotomous, tertile, quartile, and continuous values of TV viewing time in the random-effects model. The pooled analysis for dichotomous time demonstrated that CVD risk was significantly higher in the longer than shorter viewing (HR 1.28; p = 0.02). In the meta-analysis for tertile time, CVD risk was significantly higher in the longest than shortest tertile (T1) (HR 1.26; p = 0.0006), but there was no significant difference between the middle tertile and T1 (p = 0.51). The meta-analysis for quartile time indicated that CVD risk was significantly higher in the longest than shortest quartile (Q1) (HR 1.32; p = 0.0007), but there were no significant differences between the second longest quartile and Q1 (p = 0.12) and between the second shortest quartile and Q1 (p = 0.60). In the meta-analysis for continuous time, longer viewing was significantly associated with higher CVD risk (HR per 1-h/day increment; 1.06; p = 0.005). In conclusion, longer TV viewing time is significantly associated with higher CVD risk.

Latent Profiles Based on Light Physical Activity, Sedentary Behavior, Perceived Body Shape, and Body Mass Index in Patients with Dyslipidemia Influence Their Quality of Life

Despite the increasing prevalence and economic burden of dyslipidemia in South Korea, we have little data on the physical activity of patients. Thus, we aimed to investigate how quality of life among patients with dyslipidemia is influenced by a combination of the following variables: light physical activity (PA), sedentary behavior (SB), perceived body shape, and body mass index (BMI). We examined data from the Sixth Korean National Health and Nutrition Examination Survey (KNHANES VI 2015), collected in 2015 by the Korean Centers for Disease Control and Prevention. The analysis included 534 individuals with dyslipidemia out of 7380 survey participants. Latent profile analysis identified three latent classes of individuals based on their physical profiles. Class 1 patients (active; n = 48) were more active, possessed more positive views of their body shape, were less sedentary, and had a lower BMI than Class 3 patients (inactive; n = 154). Class 2 patients (moderate; n = 331) had profiles in between the other two classes. Additionally, Class 1 and 2 patients had better quality of life than Class 3 patients. Our results suggest that promoting light PA and altering perceived body shape through counselling may improve quality of life in patients with dyslipidemia.

Associations of sedentary time and self-reported television time during pregnancy with incident gestational diabetes and plasma glucose levels in women at risk of gestational diabetes in the UK

BACKGROUND

Sedentary time is associated with increased risk of type 2 diabetes, but the association between objectively measured sedentary time and incident gestational diabetes mellitus (GDM) has not been tested. The purpose of this paper is to test associations between objectively measured sedentary time and self-reported television time during pregnancy with incident GDM and plasma glucose levels among women at high risk for GDM.

METHODS

At 20 weeks' gestation, pregnant women (n = 188) in the North East of England with a risk factor for GDM wore an activPAL accelerometer and reported their usual television time. Participants underwent a standard oral glucose tolerance test at 24-28 weeks' gestation. Regression analyses were used to test for associations of total and prolonged sedentary time, breaks in sedentary time, and television time with GDM and fasting and 2-h glucose levels. Interaction terms were applied to examine whether the association between each indicator of sedentary time and glucose levels differed by GDM status.

RESULTS

Total sedentary time (hours/day) was not associated with incident GDM (OR 1.00 (95%CI 1.00, 1.01)). The association between total sedentary time and glucose levels depended on GDM status: sedentary time was associated with fasting (β = 0.16 (95%CI 0.01, 0.31)) and 2-h (β = 0.15 (95%CI 0.01, 0.30)) glucose levels for those without GDM, while breaks in sedentary time were associated with lower fasting (β = - 0.55 (95%CI - 0.92, - 0.17)) and 2-h (β = - 0.40 (95%CI - 0.77, - 0.03)) glucose levels for those with GDM. Prolonged sedentary time was associated with higher fasting glucose levels regardless of GDM status (β 0.15 (0.01, 0.30)). Television time was associated with development of GDM (OR 3.03 (95%CI 1.21, 7.96)) but not with plasma glucose levels.

CONCLUSIONS

This is the first study to test associations between posture-based measures of sedentary time during pregnancy and GDM and glucose levels. The findings presented here suggest the possible importance of minimizing or breaking up sedentary time for the management of glucose levels during pregnancy, at least among women at high risk of GDM. Further research is needed to understand the different roles of total sedentary time and television time in the development of GDM.

Benefits of 8-wk Mindfulness-based Stress Reduction or Aerobic Training on Seasonal Declines in Physical Activity

Mindfulness-based stress reduction (MBSR) and aerobic exercise training (AET) programs improve health and well-being. Exercise participation has been related to mindfulness and may be altered by MBSR training.

Wrist-specific accelerometry methods for estimating free-living physical activity

OBJECTIVES

To compare accelerometry-derived estimates of physical activity from 9 wrist-specific predictive models and a reference hip-specific method.

DESIGN

Prospective cohort repeated measures study.

METHODS

110 participants wore an accelerometer at wrist and hip locations for 1 week of free-living. Accelerometer data from three axes were used to calculate physical activity estimates using existing wrist-specific models (3 linear and 6 artificial neural network models) and a reference hip-specific method. Estimates of physical activity were compared to reference values at both epoch (≤60-s) and weekly levels.

RESULTS

9044h were analysed. Physical activity ranged from 7 to 96min per day of moderate-to-vigorous physical activity (MVPA). Method of analysis influenced determination of sedentary behaviour (<1.5 METs), light physical activity (1.5 to <3 METs) and MVPA (>3 METs) (p<0.001, respectively). All wrist-specific models produced total weekly MVPA values that were different to the reference method. At the epoch level, Hildebrand et al. (2014) produced the strongest correlation (r=0.69, 95%CI: 0.67-0.71) with tightest ratio limits of agreement (95%CI: 0.53-1.30) for MVPA, and highest agreement to predict MVPA (94.1%, 95%CI: 94.0-94.1%) with sensitivity of 63.1% (95%CI: 62.6-63.7%) and specificity of 96.0% (95%CI: 95.9-96.0%).

CONCLUSIONS

Caution is required when comparing results from studies that use inconsistent analysis methods. Although a wrist-specific linear model produced results that were most similar to the hip-specific reference method when estimating total weekly MVPA, modest absolute and relative agreement at the epoch level suggest that additional analysis methods are required to improve estimates of physical activity derived from wrist-worn accelerometers.

Relationship Between Sitting Time, Physical Activity, and Metabolic Syndrome Among Adults Depending on Body Mass Index (BMI)

Background

The aim of this study was to assess the possible relationship between sitting time and physical activity and the risk of occurrence of metabolic syndrome and its components. Analyses were conducted in the whole sample, and with stratification according to BMI. We have formulated a hypothesis that individuals with different BMIs have different responses to metabolic health modifiers such as physical activity and sitting time.

Material/Methods

Altogether, the data from 10 367 participants from urban and rural areas, aged 37–66 years were used in the study (7479 of whom were overweight or obese). The definition of metabolic syndrome devised by the IDF Joint Interim Statement criteria using an ethnic-specific cut-off point for waist circumference as the central obesity criterion was used.

Results

In all analyzed BMI groups, longer sitting time was only associated with abdominal obesity (all p for trend <0.05). In participants declaring low physical activity levels, the risk of metabolic syndrome and abnormal triglycerides concentration was higher compared to those declaring high physical activity, regardless of BMI (all p for trend <0.05). In the group with overweight or obesity, low physical activity was associated with a higher risk of abdominal obesity (p for trend <0.05), increased glucose concentration (p for trend <0.05), and elevated blood pressure (p for trend <0.05). In participants with a normal BMI, these associations did not occur.

Conclusions

Our data suggest that physical activity helps preventive metabolic syndrome and its abnormal components, especially in participants who are overweight or obese.