Sedentary behaviour and risk of all-cause, cardiovascular and cancer mortality, and incident type 2 diabetes: a systematic review and dose response meta-analysis

Effects of light-intensity physical activity on cardiometabolic parameters in young adults with overweight and obesity: The SED-ACT randomized controlled crossover trial

AIMS

To investigate how a change in body position with light-intensity physical activity (PA) 'snacks' (LIPAS, alternate sitting and standing, walking or standing continuously) compared with uninterrupted prolonged sitting affects glucose metabolism and heart rate variability (HRV) parameters in young adults with overweight and obesity.

MATERIALS AND METHODS

We conducted a four-arm randomized controlled crossover trial. The following conditions were tested during an 8-h simulated workday: uninterrupted prolonged sitting (SIT), alternate sitting and standing (SIT-STAND; 2.5 h total), continuous standing (STAND), and continuous walking (1.0 mph; WALK). The primary outcome was to investigate how a change in body position (alternate sitting and standing, walking or standing continuously) compared with uninterrupted sitting affects mean 8-h glucose metabolism. Secondary outcomes included the effects on 2-h postprandial glucose concentrations, as well as on 8-h/24-h heart rate and HRV parameters, in the respective study arms. Capillary blood samples were drawn from an hyperemised earlobe in the fasted state and once every hour during each trial intervention by puncturing the earlobe with a lancet and collecting 20 μL of blood (Biosen S-Line Lab+; EKF diagnostics, Barleben, Germany). HRV was assessed for 24 h including the 8-h intervention phase, and a home phase by means of a Holter electrocardiogram. All participants received the same standardized non-relativised breakfast and lunch during the four trial visits.

RESULTS

Seventeen individuals (eight women, mean age 23.4 ± 3.3 years, body mass index 29.7 ± 3.8 kg/m2, glycated haemoglobin level 34.8 ± 3.1 mmol/mol [5.4 ± 0.3%], body fat 31.8 ± 8.2%) completed all four trial arms. Compared with SIT (89.4 ± 6.8 mg/dL), 8-h mean glucose was lower in all other conditions (p < 0.05) and this was statistically significant compared with WALK (86.3 ± 5.2 mg/dL; p = 0.034). Two-hour postprandial glucose after breakfast was approximately 7% lower for WALK compared with SIT (p = 0.002). Furthermore, significant time × condition effects on HRV parameters favouring light-intensity walking were observed (p < 0.001).

CONCLUSIONS

Replacement and interruption of prolonged sitting with light-intensity walking showed a significant blood glucose-lowering effect and improved HRV during an 8-h work environment in young adults with overweight and obesity.

Association of lifestyle with sleep health in general population in China: a cross-sectional study

The concept of a healthy lifestyle is receiving increasing attention. This study sought to identify an optimal healthy lifestyle profile associated with sleep health in general population of China. An online cross-sectional survey was conducted from June to July 2022. Six healthy lifestyle factors were assessed: healthy diet, regular physical exercise, never smoking, never drinking alcohol, low sedentary behavior, and normal weight. Participants were categorized into the healthy lifestyle (5-6 factors), average (3-4 factors), and unhealthy lifestyle groups (0-2 factors). The study's primary outcome was sleep health, which included sleep quality, duration, pattern, and the presence of any sleep disorder or disturbance, including insomnia, excessive daytime sleepiness, obstructive apnea syndrome, and narcolepsy. Multivariable logistic regression analysis was applied to explore lifestyles associated with the selected sleep health outcomes. 41,061 individuals were included, forming 18.8% healthy, 63.8% average, and 17.4% unhealthy lifestyle groups. After adjusting for covariates, participants with healthy lifestyle were associated with a higher likelihood of good sleep quality (OR = 1.56, 95% CI = 1.46-1.68), normal sleep duration (OR = 1.60, 95% CI = 1.49-1.72), healthy sleep pattern (OR = 2.15, 95% CI = 2.00-2.31), and lower risks of insomnia (OR = 0.66, 95% CI = 0.61-0.71), excessive daytime sleepiness (OR = 0.66, 95% CI = 0.60-0.73), and obstructive apnea syndrome (OR = 0.40, 95% CI = 0.37-0.43), but not narcolepsy (OR = 0.92, 95% CI = 0.83-1.03), compared to those with unhealthy lifestyle. This large cross-sectional study is the first to our knowledge to quantify the associations of a healthy lifestyle with specific aspects of sleep health. The findings offer support for efforts to improve sleep health by modulating lifestyle.

Unveiling metabolic dysfunction-associated fatty liver disease: Knowledge gaps and attitudes among Lebanese university students

BACKGROUND

Metabolic dysfunction-associated fatty liver disease (MAFLD) is a rapidly growing global health problem. Despite its growing incidence and potential for significant repercussions, MAFLD is still widely misunderstood and underdiagnosed.

AIM

The purpose of this study was to investigate MAFLD-related knowledge, attitudes, and risk profiles among university students aged 17 to 26.

METHODS

A cross-sectional study with 406 university students in Lebanon, equally distributed among males and females, was conducted using a questionnaire that includes demographics, medical information, dietary habits, physical activity, and MAFLD-related knowledge and attitudes.

RESULTS

The findings demonstrated a significant lack of knowledge regarding MAFLD, with more than half of participants (54.7%) having no prior knowledge of the illness. Students exhibited unhealthy lifestyle behaviors such as smoking (68%), insufficient physical exercise (44.1%), and poor food habits (52.5%). Having a family history of heart disease, personal history of diabetes mellitus, a balanced diet and prior knowledge of the disease were associated with a higher knowledge score (p<0.05). A higher attitude score existed among those who have a personal or family history of chronic diseases and those who have a prior negative impression about the disease, prior knowledge of the disease, and those who are physically active (p<0.05).

CONCLUSION

Despite knowledge gaps, university students in Lebanon have, in general, an appropriate and positive attitude towards MAFLD. We recommend the introduction of focused educational interventions to address the necessity of lifestyle changes among university students and the community as a whole. Developing comprehensive MAFLD prevention methods requires future studies in different age groups and demographics.

Synergistic effects of COVID-19 pandemic and sedentary lifestyles on obesity rates among South Korean adults

Since March 2020, South Korea has implemented social distancing measures to reduce the spread of the coronavirus disease (COVID-19). These policies resulted in significant changes in the lifestyle of Korean adults, including spending more time indoors and experiencing increased sedentary time during the pandemic. This study aimed to investigate the combined influence of sedentary lifestyle and the COVID-19 pandemic on obesity rates among adults residing in South Korea. Data were obtained from the 2018-2020 Korea National Health and Nutrition Examination Survey (KNHANES). Multiple logistic regression was used to analyze the synergistic effects of a sedentary lifestyle and COVID-19 on obesity. The prevalence of sedentary lifestyles among the participants increased from 30.4% pre-COVID-19 to 36.6% during the pandemic. Furthermore, the obesity rates were raised independently by COVID-19 (OR: 1.16, 95% CI 1.04-1.30) and by a sedentary lifestyle (OR = 1.17, 95% CI 1.04-1.31). A synergistic effect of a sedentary lifestyle and COVID-19 on obesity was identified (OR: 1.57, 95% CI 1.30-1.85). COVID-19 and a sedentary lifestyle significantly increased the risk of obesity in South Korean adults. Moreover, the combined synergistic effects of these risk factors were too substantial to be disregarded by merely summing their individual effects on obesity.

Validity and reliability of self-reported methods for assessment of 24-h movement behaviours: a systematic review

BACKGROUND

Time spent in sleep, sedentary behaviour (SB), and physical activity are exhaustive and mutually exclusive parts of a 24-h day that need to be considered in a combination. The aim of this study was to identify validated self-reported tools for assessment of movement behaviours across the whole 24-h day, and to review their attributes and measurement properties.

METHODS

The databases PubMed, Scopus, and SPORTDiscus were searched until September 2023. Inclusion criteria were: (i) published in English language, (ii) per-reviewed paper, (iii) assessment of self-reported time spent in sleep, SB, and physical activity, (iv) evaluation of measurement properties of all estimates across the full 24-h day, and (v) inclusion of adolescents, adults, or older adults. The methodological quality of included studies was assessed using the Consensus-based Standards for the selection of health Measurement Instruments checklist.

RESULTS

Our search returned 2064 records. After studies selection, we included 16 articles that reported construct validity and/or test-retest reliability of 12 unique self-reported tools - eight questionnaires, three time-use recalls, and one time-use diary. Most tools enable assessment of time spent in sleep, and domain-specific SB and physical activity, and account that sum of behaviours should be 24 h. Validity (and reliability) correlation coefficients for sleep ranged between 0.22 and 0.69 (0.41 and 0.92), for SB between 0.06 and 0.57 (0.33 and 0.91), for light-intensity physical activity between 0.18 and 0.46 (0.55 and 0.94), and for moderate- to vigorous-intensity physical activity between 0.38 and 0.56 (0.59 and 0.94). The quality of included studies being mostly fair-to-good.

CONCLUSIONS

This review found that only a limited number of validated self-reported tools for assessment of 24-h movement behaviours are currently available. Validity and reliability of most tools are generally adequate to be used in epidemiological studies and population surveillance, while little is known about adequacy for individual level assessments and responsiveness to behavioural change. To further support research, policy, and practice, there is a need to develop new tools that resonate with the emerging 24-h movement paradigm and to evaluate measurement properties by using compositional data analysis.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42022330868.

Joint associations of leisure time physical activity and screen sitting time with long-term sickness absence due to mental and musculoskeletal diseases: a registry linked follow-up study

OBJECTIVES

To examine joint associations of leisure-time physical activity (LTPA) and screen sitting time with subsequent sickness absence among the adult population.

STUDY DESIGN

Registry linked follow-up study.

METHODS

A representative sample of Finnish adults (n = 10,300) were asked to fill out a questionnaire for the FinHealth 2017 survey. Self-reported LTPA was classified into three groups: inactive, moderately active, and active, and screen sitting time into two groups: 3 h or less and over three hours a day, yielding a six-category variable for the joint analyses. Questionnaire data were linked to the Finnish Social Insurance Institution's register data on sickness benefits (over 9 days), including diagnoses (follow-up 2.9 years). The analytical samples were restricted to working age (18-64 years), which included 5098 participants. Associations were examined using logistic regression analysis adjusting for covariates with SPSS 29.

RESULTS

The inactive and high sitting time had a higher risk for sickness absence due to mental disorders (OR 2.07, 95% CI 1.03-4.18) compared with the physically active, low-sitting time group. Additionally, the inactive and low sitting time (OR 1.69 95% CI 1.12-2.55) and the moderately active and high-sitting time groups (OR 2.06 95% CI 1.15-3.67) had a higher risk. No significant associations were found for all-cause and musculoskeletal diseases sickness absence.

CONCLUSION

Employers and policymakers could support reducing sitting in front of a screen and increase LTPA outside working hours to prevent mental health problems and related sickness absences.

Associations between Recreational Screen Time and Brain Health in Middle-Aged and Older Adults: A Large Prospective Cohort Study

OBJECTIVES

To investigate the associations of recreational screen time with risks of brain-related disorders (dementia, stroke, and Parkinson's disease) and neuroimaging features.

DESIGN

Prospective cohort study.

SETTING AND PARTICIPANTS

A total of 407,792 participants from the UK Biobank who were free of dementia, stroke, or Parkinson's disease at enrollment (2006-2010).

METHODS

TV viewing and time spent using the computer were self-reported at baseline. Among a subsample of 40,692 participants, neuroimaging features were measured by magnetic resonance imaging in 2014. Data were analyzed using Cox proportional hazard models, restricted cubic spline models, and general linear regression models.

RESULTS

During a median follow-up of 12.6 years, 5227 incident dementia, 6822 stroke, and 2308 Parkinson's disease cases were identified. Compared with TV viewing >0-1 h/day, watching TV ≥5 h/day was associated with higher risks of dementia [hazard ratio (HR), 1.44; 95% confidence interval (CI), 1.28-1.62], stroke (HR, 1.12; 95% CI, 1.01-1.25), and Parkinson's disease (HR, 1.28; 95% CI, 1.06-1.54). Moreover, we observed inverse associations between TV viewing time and both gray matter volume and hippocampus volume (Ptrend <.001). However, we did not observe the significant associations between discretional computer use and brain-related disorders or neuroimaging features.

CONCLUSIONS AND IMPLICATIONS

Our findings suggest that high TV viewing time is associated with increased risk of various brain-related disorders, highlighting recreational TV viewing could have an important impact on brain-related health.

Lifestyle factors as determinants of atherosclerotic cardiovascular health

A sedentary lifestyle, low levels of physical activity and fitness, poor dietary patterns, and psychosocial stress are strongly associated with increased morbidity and mortality from atherosclerotic cardiovascular disease (ASCVD). Conversely, engaging in regular physical activity, maintaining optimal fitness levels, adhering to a heart-healthy dietary pattern, effectively managing body weight, ensuring adequate sleep, implementing stress-reduction strategies, and addressing psychosocial risk factors are associated with a reduced risk of ASCVD. This comprehensive review synthesizes current evidence from large observational studies and randomized controlled trials on lifestyle factors as determinants of ASCVD health. It also briefly reviews mechanistic insights into how factors such as low shear stress, increased reactive oxygen species production, chronic inflammation, platelets and coagulation activation, endothelial dysfunction, and sympathetic hyperactivity contribute to the initiation and exacerbation of ASCVD risk factors. These include obesity, hyperglycemia, type 2 diabetes, hypertension, and dyslipidemia, subsequently leading to the development and progression of atherosclerosis, ultimately resulting in chronic ASCVD or acute cardiovascular events. To bridge the translational gap between epidemiologic and trial-based evidence and clinical practice, practical recommendations are summarized to facilitate the translation of scientific knowledge into actionable interventions to promote ASCVD health. Acknowledged is the gap between the evidence-based knowledge and adoption within healthcare systems, which remains a crucial objective in advancing cardiovascular health at the population level.

Sitting time, physical activity and mortality: a cohort study in low-income older Americans

INTRODUCTION

Physical inactivity and sedentary behavior are recognized as independent risk factors for many diseases. However, studies investigating their associations with total and cause-specific mortality in low-income and Black populations are limited, particularly among older adults.

METHODS

A prospective cohort study was conducted among 8,337 predominantly low-income and Black Americans aged ≥65 years residing in the southern United States. Participants reported their daily sitting time and leisure-time physical activity (LTPA) at baseline (2002-2009), and mortality data were collected through 2019. Analysis was conducted from September 2022 to October 2023.

RESULTS

During a median follow-up of 12.25 years, nearly 50% (n = 4,111) were deceased. A prolonged sitting time (>10 hours/day vs. <4 hours/day) was associated with an elevated all-cause mortality (HR, 1.15; 95% CI, 1.04-1.27) after adjusting for LTPA and other potential confounders. LTPA was associated with a reduced risk of all-cause mortality, with an adjusted HR of 0.75 (95% CI 0.64, 0.88) associated with 150 to 300 minutes per week of moderate-intensity physical activity. Individuals who were physically inactive and had a sitting time of >10 h/d had the highest mortality risk (HR, 1.48; 95% CI, 1.23-1.78), compared with those who were physically active and had low sitting time. These associations were more pronounced for mortality due to cardiovascular diseases (CVD).

CONCLUSIONS

High sitting time is an independent risk factor for all-cause and CVD mortality, and LTPA could partially attenuate the adverse association of prolonged sitting time with mortality.

A Physical Activity and Sitting Time Balance Index and All-Cause Mortality Risk

INTRODUCTION

Achieving a healthier balance of more time spent in physical activity (PA) and less time in sedentary behaviour is now widely advocated for achieving multiple health benefits. This study introduces a Physical Activity and Sitting Time Balance Index (PASTBI), a potential risk identification tool addressing the interplay between PA and sedentary behaviour; and aims to explore its association with the risk of all-cause mortality in Australian adults.

METHODS

This prospective cohort study analysed the Australian Diabetes, Obesity and Lifestyle Study (AusDiab) data on 5,836 Australian adults. The PASTBI was calculated by dividing the total duration of moderate-vigorous intensity PA (minutes/day) by the duration of sitting time (ST) (hours/day), both self-reported at baseline (2004-05). The PASTBI was expressed in quartiles ranging from Q1 - low PA/high ST to Q4 - high PA/low ST. The association between PASTBI and all-cause mortality was explored (in 2022) using the Cox proportional hazards regression models adjusted for socio-demographics, lifestyle factors, waist circumference, and the number of comorbidities.

RESULTS

During 78,406 person-years of follow-up (median follow-up of 14.3 years), there were 885 deaths (15%). In the fully adjusted model, compared to those in the highest PASTBI category (Quartile 4 - high PA/low ST), participants from the lowest PASTBI category (Quartile 1 - low PA/high ST) were at a higher risk of all-cause mortality [HR (95% CI) = 1.47 (1.21-1.79)].

CONCLUSIONS

A less favourable balance of time spent in PA and ST (as characterized by a parsimonious PASTBI index approach) was associated with a higher risk of all-cause mortality.

Sedentary Behaviour and Fall-related Injuries in Aging Adults: Results from the Canadian Longitudinal Study on Aging (CLSA)

Background

Falls, and more specifically, fall-related injuries, are costly to the healthcare system and can harm one's autonomy.

Objectives

To study the impact of sedentary behaviour associated with fall-related injuries and how a change in sedentary behaviour may impact the risk of a fall-related injury.

Design

From baseline to the first follow-up, cross-sectional and longitudinal data analysis from the Canadian Longitudinal Study of Aging (CLSA) cohort.

Participants

CLSA data from 43,558 Canadians aged 45-85 were included in this study.

Measurements

At baseline and follow-up, sedentary behaviour time was categorized as low (<1,080 minutes/week), moderate (1,080-1,440), or high (>1,440). Sedentary behaviour was estimated via the Physical Activity Scale for the Elderly (PASE). At follow-up, participants were dichotomized as either increased or decreased/no change in sedentary behaviour according to their categorical change between time points.

Results

Sedentary behaviour was associated with fall-related injuries independently of age, sex, number of chronic conditions, and total physical activity levels OR (95%CI) 1.10 (1.05-1.15). In contrast, a change in sedentary behaviour was not associated with the risk of fall-related injury 1.00 (0.92-1.01).

Conclusion

A higher level of sedentary behaviour is associated with injurious falls for people between 40 and 80 years old. However, a short-term change in sedentary behaviour does not influence the risk of injury-related falls. Despite the results, a more precise measure of sedentary behaviour is needed for epidemiology studies to capture changes over time better.

TET3 Contributes to Exercise-Induced Functional Axon Regeneration and Visual Restoration

Axons have intrinsically poor regenerative capacity in the mature central nervous system (CNS), leading to permanent neurological impairments in individuals. There is growing evidence that exercise is a powerful physiological intervention that can obviously enhance cell rejuvenate capacity, but its molecular mechanisms that mediate the axonal regenerative benefits remain largely unclear. Using the eye as the CNS model, here it is first indicated that placing mice in an exercise stimulation environment induced DNA methylation patterns and transcriptomes of retinal ganglion cell, promoted axon regeneration after injury, and reversed vision loss in aged mice. These beneficial effects are dependent on the DNA demethylases TET3-mediated epigenetic effects, which increased the expression of genes associated with the regenerative growth programs, such as STAT3, Wnt5a, Klf6. Exercise training also shows with the improved mitochondrial and metabolic dysfunction in retinas and optic nerves via TET3. Collectively, these results suggested that the increased regenerative capacity induced by enhancing physical activity is mediated through epigenetic reprogramming in mouse model of optic nerve injury and in aged mouse. Understanding the molecular mechanism underlying exercise-dependent neuronal plasticity led to the identification of novel targets for ameliorating pathologies associated with etiologically diverse diseases.

Evaluation of a Virtual Tai Chi Program for Older Veterans at Risk of Loneliness or Physical Deconditioning: A Quality Improvement Project

This Quality Improvement project evaluated the implementation of a virtual Tai Chi program for older Veterans (OVs) at risk of loneliness and/or physical deconditioning. A 12-week Tai Chi course was conducted virtually at three Veterans Affairs sites using VA Video Connect (VVC). Changes in physical function based on the 30-Second Chair Stand (30CST) and loneliness based on the De Jong Gierveld Loneliness Scale (DJGS) were measured, as were the OVs' satisfaction and adherence. Of 109 OVs who enrolled, 74 completed the program with a mean attendance rate of 84%. Completers demonstrated a statistically significant improvement in the 30CST, and those who were moderately or severely lonely at baseline saw a statistically significant improvement in the DJGS. Course evaluations were generally very positive. Results suggest that a virtual Tai Chi program is an effective and very satisfying intervention for OVs at risk of loneliness or physical deconditioning.

Physical activity, sedentary behavior and microbiome: A systematic review and meta-analysis

BACKGROUND

The effects of physical activity and sedentary behavior on human health are well known, however, the molecular mechanisms are poorly understood. Growing evidence points to physical activity as an important modulator of the composition and function of microbial communities, while evidence of sedentary behavior is scarce. We aimed to synthesize and meta-analyze the current evidence about the effects of physical activity and sedentary behavior on microbiome across different body sites and in different populations.

METHODS

A systematic search in PubMed, Web of Science, Scopus and Cochrane databases was conducted until September 2022. Random-effects meta-analyses including cross-sectional studies (active vs. inactive/athletes vs. non-athletes) or trials reporting the chronic effect of physical activity interventions on gut microbiome alpha-diversity in healthy individuals were performed.

RESULTS

Ninety-one studies were included in this systematic review. Our meta-analyses of 2632 participants indicated no consistent effect of physical activity on microbial alpha-diversity, although there seems to be a trend toward a higher microbial richness in athletes compared to non-athletes. Most of studies reported an increase in short-chain fatty acid-producing bacteria such as Akkermansia, Faecalibacterium, Veillonella or Roseburia in active individuals and after physical activity interventions.

CONCLUSIONS

Physical activity levels were positively associated with the relative abundance of short-chain fatty acid-producing bacteria. Athletes seem to have a richer microbiome compared to non-athletes. However, high heterogeneity between studies avoids obtaining conclusive information on the role of physical activity in microbial composition. Future multi-omics studies would enhance our understanding of the molecular effects of physical activity and sedentary behavior on the microbiome.

Joint association of sedentary time and physical activity with abnormal heart rate recovery in young and middle-aged adults

BACKGROUND

Abnormal heart rate recovery (HRR), representing cardiac autonomic dysfunction, is an important predictor of cardiovascular disease. Prolonged sedentary time (ST) is associated with a slower HRR. However, it is not clear how much moderate-to-vigorous physical activity (MVPA) is required to mitigate the adverse effects of sedentary behavior on HRR in young and middle-aged adults. This study aimed to examine the joint association of ST and MVPA with abnormal HRR in this population.

METHODS

A cross-sectional analysis was conducted on 1253 participants (aged 20-50 years, 67.8% male) from an observational study assessing cardiopulmonary fitness in Fujian Province, China. HRR measured via cardiopulmonary exercise tests on a treadmill was calculated as the difference between heart rate at peak exercise and 2 min after exercise. When the HRR was ≤ 42 beats·minute-1 within this time, it was considered abnormal. ST and MVPA were assessed by the IPAQ-LF. Individuals were classified as having a low sedentary time (LST [< 6 h·day-1]) or high sedentary time (HST [≥ 6 h·day-1]) and according to their MVPA level (low MVPA [0-149 min·week-1], medium MVPA [150-299 min·week-1], high MVPA [≥ 300 min·week-1]). Finally, six ST-MVPA groups were derived. Associations between ST-MVPA groups with abnormal HRR incidence were examined using logistic regression models.

RESULTS

53.1% of the young and middle-aged adults had less than 300 min of MVPA per week. In model 2, adjusted for possible confounders (e.g. age, sex, current smoking status, current alcohol consumption, sleep status, body mass index), HST was associated with higher odds of an abnormal HRR compared to LST (odds ratio (OR) = 1.473, 95% confidence interval (CI) = 1.172-1.852). Compared with the reference group (HST and low MVPA), the HST and high MVPA groups have a lower chance of abnormal HRR (OR, 95% CI = 0.553, 0.385-0.795). Compared with individuals with HST and low MVPA, regardless of whether MVPA is low, medium, or high, the odds of abnormal HRR in individuals with LST is significantly reduced (OR, 95% CI = 0.515, 0.308-0.857 for LST and low MVPA; OR, 95% CI = 0.558, 0.345-0.902 for LST and medium MVPA; OR, 95% CI = 0.476, 0.326-0.668 for LST and high MVPA).

CONCLUSION

Higher amounts of MVPA appears to mitigate the increased odds of an abnormal HRR associated with HST for healthy young and middle-aged adults.

Device-measured sedentary time and intensity-specific physical activity in relation to all-cause and cardiovascular disease mortality: the UK Biobank cohort study

BACKGROUND AND AIMS

Understanding the amounts of intensity-specific movement needed to attenuate the association between sedentary time and mortality may help to inform personalized prescription and behavioral counselling. Herein, we examined the joint associations of sedentary time and intensity-specific physical activity with all-cause and cardiovascular disease (CVD) mortality.

METHODS

Prospective cohort study including 73,729 adults from the UK Biobank who wore an Axivity AX3 accelerometer on their dominant wrist for at least 3 days, being one a weekend day, between June 2013 and December 2015. We considered the median tertile values of sedentary time and physical activity in each intensity band to determine the amount of physical activity needed to attenuate the association between sedentary time and mortality.

RESULTS

During a median of 6.9 years of follow-up (628,807 person-years), we documented 1521 deaths, including 388 from CVD. Physical activity of any intensity attenuated the detrimental association of sedentary time with mortality. Overall, at least a median of 6 min/day of vigorous physical activity, 30 min/day of MVPA, 64 min/day of moderate physical activity, or 163 min/day of light physical activity (mutually-adjusted for other intensities) attenuated the association between sedentary time and mortality. High sedentary time was associated with higher risk of CVD mortality only among participants with low MVPA (HR 1.96; 95% CI 1.23 to 3.14).

CONCLUSIONS

Different amounts of each physical activity intensity may attenuate the association between high sedentary time and mortality.

Associations between domains of sedentary behavior, well-being, and quality of life - a cross-sectional study

The importance of reducing sedentary behavior (SB) in the prevention of mortality and chronic and mental diseases is scientifically well grounded, but SB can be accumulated in diverse domains of life, such as leisure-time SB, transport between home/work/school when sitting (transport-related SB), or in occupational settings such as working or studying (occupational SB), and the associations for each domain of SB with well-being measures and quality of life are still underexplored from a positive perspective. Through a cross-sectional investigation, we collected data from 584 participants who completed a questionnaire throughout November 2021 and with Spearman correlation test, analysed the associations between SB in three different domains with psychological well-being, satisfaction with life, and quality of life. Our results indicated that after adjustment for physical activity, sex, body mass index, smoking history, chronic disease status, financial perception, quality/duration of sleep and university group, in younger adults (18 to 24 years old), leisure-time SB was negatively related to psychological well-being (rho = -0.255; p = 0.008), and in adults (25 to 64 years old), occupational SB was negatively related to satisfaction with life (rho = -0.257; p < .001) and the mental component of quality of life (rho = -0.163; p = 0.027). Our findings highlight the idea that not all SB is built the same and that future strategies to reduce SB from people's lives must target specific domains of SB according to the age group when aiming to improve well-being and quality of life.

Sex Differences in Physical Activity Levels and Sitting Time in Patients With Atrial Fibrillation

PURPOSE

While research demonstrates low levels of physical activity (PA) among adults living with atrial fibrillation (AF), there is limited evidence investigating sex differences in moderate to vigorous intensity physical activity (MVPA) and sedentary time in this population. The primary aim was to examine sex differences in MVPA levels and sitting time between women and men with AF. Secondary aims explored sex differences in sociodemographic factors, outcome expectations, and task self-efficacy toward PA levels.

METHODS

This was a subanalysis of the CHAMPLAIN-AF cohort study. Women and men with AF completed a survey, including the Short-Form International Physical Activity Questionnaire.

RESULTS

A total of 210 women (median = 66.0 yr: 95% CI, 63.5-68.0) and 409 men (median = 66.0 yr: 95% CI, 64.0-67.0) were included. No sex differences were observed in median weekly MVPA (60 min/wk: 95% CI, 0-120 in women vs 120 min/wk: 95% CI, 85-150 in men) and daily sitting time (5.5 hr/d: 95% CI, 5.0-6.0 in women vs 6.0 hr/d: 95% CI, 5.0-6.0 in men). Women engaged in significantly less vigorous-intensity PA than men ( P = .03) and demonstrated significantly lower task self-efficacy ( P < .01). Significant positive correlations in PA levels with outcome expectations (mostly weak) and task self-efficacy (mostly strong) were observed in both sexes.

CONCLUSION

Most women and men with AF did not meet the global MVPA guidelines but met the sitting time recommendation. Women presented with lower vigorous-intensity physical activity levels and confidence than men. Strategies to increase physical activity behavior, considering sociodemographic factors and task self-efficacy, are needed and may differ between sexes.

Maternal physical activity and sitting time and its association with placental morphology and blood flow during gestation: Findings from the Queensland Family Cohort study

OBJECTIVES

Antenatal exercise is associated with placental morphological alterations, however research in this area is limited. Given the emphasis on the beneficial effects of antenatal exercise, it is important to understand its effect on placental function and the relationship to foetal development. The aim of this study was to investigate the association between physical activity, sitting time, and placental outcomes measured during gestation.

DESIGN

Prospective cohort study.

METHODS

Pregnant women in the Queensland Family Cohort study self-reported physical activity at 24 and 36 weeks of gestation (n = 203) and were categorised into physical activity volume groups of nil-low (0-<500 metabolic equivalent of task·minutes/week), moderate (500-<1000 metabolic equivalent of task·minutes/week), or high-volume activity (≥1000 metabolic equivalent of task·minutes/week). Participants reported average daily sitting time, whereby excessive sitting time was considered as ≥8h/day. Placental stiffness, thickness, and uteroplacental blood flow resistance were measured by ultrasound imaging at each timepoint.

RESULTS

Physical activity volume was not associated with changes to placental morphometrics or uteroplacental blood flow resistance at 24 or 36 weeks of gestation. Excessive sitting time at 36 weeks was associated with greater placental stiffness (p = 0.046), and a lower umbilical artery pulsatility index (p = 0.001).

CONCLUSIONS

Placental tissue stiffness and umbilical artery resistance were altered in late gestation with higher maternal sitting time but not with physical activity volume. Overall, excessive sitting time may be a risk for suboptimal placental function and could be an important focus for antenatal care.

Association between sedentary behavior, screen time and metabolic syndrome among Chinese children and adolescents

BACKGROUND

The aim of the study was to investigate the relationship between sedentary behavior, screen time and MetS among Chinese children and adolescents aged 7-17 years. Data was obtained from the China National Nutrition and Health Surveillance of Children and Lactating Mothers in 2016-2017.

METHODS

Data on sedentary time, screen time, and MetS indicators were obtained through physical and health questionnaires, anthropometric measurements, and clinical examinations. MetS was defined according to the Cook's criteria. Wilcoxon rank sum test and chi-square test were applied for comparisons of measurement data and counting data, respectively. The relationship between sedentary time, screen time, and MetS and its components was analyzed using a multivariate logistic regression model.

RESULTS

The prevalence of MetS among 7-17-year-old students in 2016-2017 was 5.45%. Compared to those with low sedentary behavior, in high sedentary behavior groups, the prevalence of abdominal obesity, high TG, low HDL-C, and MetS was high in boys, and the prevalence of abdominal obesity, high TG, hyperglycemia, and MetS was high in girls. Moreover, for those who reported ≥ 3 h/day of screen time, the prevalence of abdominal obesity, low HDL-C, and MetS was higher in boys, and the prevalence of abdominal obesity and MetS was higher in girls. After adjusting for confounding variables, the risks of abdominal obesity, high TG, low HDL-C, and MetS were higher in high-level sedentary time group, and the risks of abdominal obesity and MetS were 1.15 and 1.14 times higher for those who spent ≥ 3 h/day on screen time, respectively.

CONCLUSIONS

This study shows that high levels of sedentary time and screen time were associated with an increased likelihood of MetS among Chinese children and adolescents aged 7-17 years. Reducing sedentary behavior and screen time may contribute to the prevention of metabolic diseases.

Physical activity levels and sedentary behaviour according to sex, age, BMI, academic year, and country among medical students in Latin America

Physical inactivity represents a global challenge in public health, being the second most significant factor contributing to mortality. In Latin America, the prevalence of physical inactivity and sedentary behaviour is notable, affecting medical students as well, who play a crucial role as behavioural role models for the population. This study addresses the prevalence of physical activity and sedentary behaviour among medical students in Latin America during the year 2023. A total of 864 participants from 12 institutions across eight countries were surveyed using the Global Physical Activity Questionnaire. Significant variations in physical activity and sedentary behaviour were observed according to sex, age, body mass index, academic year, and country. Notably, Costa Rica exhibited the highest levels of moderate physical activity in leisure time (90 min/day). Strength training was more common among men (60 min/day) and in Argentina (60 min/day). Sedentary behaviour was higher in women (420 min/day) and during the first academic year (485 min/day). Uruguay stood out with high levels of sedentary behaviour (600 min/day). Correlations indicated positive moderate associations between academic year and moderate leisure-time PA (r:0,128, p:0,007). In conclusion, there are associations between the level of physical activity and sedentary behaviour with the variables studied in this research, with the main findings being that the female sex has more time spent in sedentary behaviour (minutes/day) and less time spent in strength training (minutes/day). Additionally, there are higher levels of sedentary behaviour in the early years of medical study compared to the later years of the program.

Physical activity and exercise health benefits: cancer prevention, interception, and survival

Physical activity (PA) has an established role in the promotion of health and fitness and the prevention of disease. Expected overall benefits include reduction of all-cause morbidity and death, weight control, improved quality of life, improved bone health and decreased falls of elderly subjects, , deeper cognition, and reduced risk of depression, anxiety, and sleeplessness. Currently, PA is a mainstay in the management of cardiovascular diseases, metabolic syndrome, diabetes, and bone health. Recently, the perception of its role in primary and secondary prevention, interception, and treatment of cancer, however, is also gaining importance. Regular walking, the simplest type of PA, is associated with reduced all-cause and cardiovascular disease mortality, and a role in cancer prevention is of increasing interest. Furthermore, PA improves the quality of life of cancer patients, attenuating side effects of chemotherapy, decreasing sarcopenia, increasing fitness, and inhibiting the recurrence and progression of some cancer types. It promotes emotional and psychological benefits in patients, inducing positive changes. While mechanisms, effective levels and useful amount of PA practice are well established in cardiology, they are yet to be fully determined in oncology. Nevertheless, PA is recommended to reduce cancer risk in the general population, and it has been introduced in programs for the prevention of second cancers. In perspective, it will help as integrative therapy in cancer patients and for cancer survivors. The number of beneficial effects in the cancer continuum is highlighted in this review.

The Best Exercise Modality and Dose to Reduce Glycosylated Hemoglobin in Patients with Type 2 Diabetes: A Systematic Review with Pairwise, Network, and Dose-Response Meta-Analyses

BACKGROUND

Persistently elevated glycosylated hemoglobin (HbA1c) is associated with a higher risk of long-term vascular complications.

OBJECTIVE

We evaluated the effect of different exercise modalities and doses on HbA1c levels in patients with type 2 diabetes.

METHODS

A systematic search for randomized controlled trials involving exercise interventions in patients with type 2 diabetes was conducted across seven electronic databases, encompassing data from their inception up to October 2023. Two independent reviewers assessed the quality of the literature. Pairwise, network, and dose-response meta-analyses using the random-effects model were conducted to analyze the effect of exercise on HbA1c levels.

RESULTS

A total of 85 randomized controlled trials with 5535 participants were included. The network meta-analysis showed that high-intensity interval training (HIIT) has the highest ranked (MD =  - 0.78% [- 8.50 mmol/mol]; 95% CrI:  - 1.04, - 0.51), followed by combined aerobic and resistance exercise (CE) (MD =  - 0.54% [- 5.90 mmol/mol]; 95% CrI: - 0.69, - 0.40), yoga (MD =  - 0.45% [- 4.92 mmol/mol]; 95% CrI: - 0.77, - 0.13), and continuous aerobic exercise (CAE) (MD =  - 0.42% [- 4.58 mmol/mol]; 95% CrI: - 0.54, - 0.30). In addition, a significant improvement in HbA1c levels can be observed when the total exercise dose reaches 840 metabolic equivalent of tasks-min/week.

CONCLUSIONS

There was low-quality evidence that HIIT, CE, yoga, and CAE may be effective treatment modalities for improving HbA1c in patients with type 2 diabetes, and there was no significant difference in efficacy. Moreover, a non-linear dose-response relationship was found for total exercise and HbA1c levels. Future research should further investigate the specific effects of different exercise doses on HbA1c levels in patients with type 2 diabetes and provide a more personalized exercise prescription.

Sedentary behaviour among elderly patients after total knee arthroplasty and its influencing factors

To understand the status of sedentary behaviour in elderly patients after total knee arthroplasty and analyse its influencing factors so as to provide a reference for developing targeted interventions. Conveniently selected elderly patients undergoing total knee arthroplasty (> 6 months) in a tertiary hospital in Jiangsu Province were investigated using a general information questionnaire, the Charlson Comorbidity Index, patients' self-reported sedentary behaviour information, the WOMAC Score, The Groningen Orthopaedic Social Support Scale, and Lee's Fatigue. The median daily sedentary time was 5.5 h (4.5 h, 6.625 h) in 166 elderly patients after total knee arthroplasty, of whom 82 (49.40%) showed sedentary behaviour (≥ 6 h per day). Logistic regression analysis showed that being retired/unemployed (OR = 8.550, 95% CI 1.732-42.207, P = 0.0084), having a CCI score ≥ 3 (OR = 9.018, 95% CI 1.288-63.119, P < 0.0001), having high WOMAC scores (OR = 1.783, 95% CI 1.419-2.238, P < 0.0001), having a high social support score (OR = 1.155, 95% CI 1.031-1.294, P = 0.0130), and having a fatigue score ≥ 5 (OR = 4.848, 95% CI 1.084-21.682, P = 0.0389) made patients more likely to be sedentary. The sedentary time of elderly patients after total knee arthroplasty is long, and sedentary behaviour is common among them. Healthcare professionals should develop targeted sedentary behaviour interventions based on the influencing factors of sedentary behaviour in order to reduce the occurrence of sedentary behaviour in elderly patients after total knee arthroplasty.

Changes in sedentary behavior in the chronic phase following stroke

BACKGROUND

Sedentary behavior increases risk for cardiovascular diseases. Little is known about sedentary behavior through the chronic phase after stroke. We aimed to describe how long and short bouts of sedentary behavior changed over the first three years after stroke and if cognition at baseline was an independent risk factor for sedentary behavior.

METHODS

This is a sub-study of the Norwegian cognitive impairment after stroke (Nor-COAST) study, a multicenter study recruiting patients with acute stroke. Sedentary behavior was monitored with a thigh-worn sensor (ActivPal3®), at three-, 18- and 36-months post stroke. Stroke severity was assessed by National Institutes of Health Stroke Scale (NIHSS) and cognition by Montreal cognitive assessment (MoCA). Mixed model analysis with mean number of sedentary minutes accumulated daily as the dependent variable was repeated for all four zones (<30min, 30-60min, 60-90min, >90min) and for total sedentary time.

RESULTS

The number of included participants was 528 (mean age 71.4, NIHSS on day 1, 2.7). The total amount of sedentary time accumulated between 08.00-22.00 increased significantly from about 9.8 hours at three months to 10.1 hours at 36 months post stroke (p=0.002). Patient characteristics associated with prolonged duration of the sedentary bouts and sedentary time were age, high BMI, comorbidities, and impaired physical function. No significant associations between MoCA score and sedentary time were found.

CONCLUSION

The participants became increasingly sedentary and had fewer breaks in sedentary time from three to 36 months after stroke. Baseline cognition was not related to later sedentary behavior.

Modulating the Expression of Exercise-induced lncRNAs: Implications for Cardiovascular Disease Progression

Recent research shows exercise is good for heart health, emphasizing the importance of physical activity. Sedentary behavior increases the risk of cardiovascular disease, while exercise can help prevent and treat it. Additionally, physical exercise can modulate the expression of lncRNAs, influencing cardiovascular disease progression. Therefore, understanding this relationship could help identify prospective biomarkers and therapeutic targets pertaining to cardiovascular ailments. This review has underscored recent advancements concerning the potential biomarkers of lncRNAs in cardiovascular diseases, while also summarizing existing knowledge regarding dysregulated lncRNAs and their plausible molecular mechanisms. Additionally, we have contributed novel perspectives on the underlying mechanisms of lncRNAs, which hold promise as potential biomarkers and therapeutic targets for cardiovascular conditions. The knowledge imparted in this review may prove valuable in guiding the design of future investigations and furthering the understanding of lncRNAs as diagnostic, prognostic, and therapeutic biomarkers for cardiovascular diseases.

Large-scale greenway exposure reduces sedentary behavior: A natural experiment in China

As a global public health problem, sedentary behavior has attracted more and more attention. Although numerous studies have demonstrated many benefits of green spaces to health, causal evidence on how green spaces affect people's sedentary behavior is scarce. This study used a natural experiment to evaluate the impact of greenway intervention on sedentary behavior. Two waves of data were collected in 2016 and 2019 (before and after the intervention) at East Lake Greenway (102-km-long) in Wuhan, China, with 1020 participants in 52 neighborhoods. We adopted three major methods to evaluate the impact of greenway intervention on sedentary behavior, including Propensity Score Matching and difference-in-difference (PSM-DID) method (with both individual and neighborhood variables to match samples), continuous treatment DID method (with distance to the greenway as the continuous treatment), and mediation analysis (with moderate to vigorous physical activity or MVPA, and walking time as the mediator). The results revealed that the greenway intervention significantly reduced participants' sedentary time and the intervention has a distance decay effect. The closer to the greenway, the greater decrease in sedentary time after the greenway opening. Furthermore, we found that MVPA and walking time mediate the impact of the greenway intervention on the change in sedentary behavior. The effect of greenway intervention was more beneficial for those under the age of 60, those who were employed, or those who were married. Our findings provided robust evidence that exposure to urban greenways affects sedentary behavior and such green infrastructures help protect public health in high-density urban areas.

Acceptability of Performing Resistance Exercise Breaks in the Workplace to Break Up Prolonged Sedentary Time: A Randomized Control Trial in U.S. Office Workers and Students

We investigated the acceptability of bodyweight resistance exercise breaks (REB) to disrupt prolonged sedentary behavior in the workplace. Twenty-nine individuals completed a REB, where they performed 3-min REB 4, 8, and 16 times on days 1-2, 3-4, and 5 of the workweek, respectively, and a control condition (i.e., SIT). Productivity was assessed on days 1 and 5 each week. The acceptability of each REB frequency was assessed. When asked to complete 4, 8, and 16 REB, participants completed (mean values) 3.2, 6.2, and 9.2 REB/day, respectively. Moreover, 88%, 40%, and 9% of participants expressed that the 4-, 8-, and 16-REB frequencies were acceptable, respectively. Decision-making ability and concentration levels increased from day 1-5 of the REB week (p=0.048) but were stable during SIT. REB (4/day) are highly acceptable and could be a promising intervention strategy for reducing occupational sitting, thus decreasing sedentary-behavior-induced risk.

Short, frequent, light-intensity walking activity improves postprandial vascular-inflammatory biomarkers in people with type 1 diabetes: The SIT-LESS randomized controlled trial

AIM

To examine the effect of interrupting prolonged sitting with short, frequent, light-intensity activity on postprandial cardiovascular markers in people with type 1 diabetes (T1D).

MATERIALS AND METHODS

In a randomized crossover trial, 32 adults with T1D (mean ± SD age 28 ± 5 years, glycated haemoglobin 67.9 ± 12.6 mmol/mol, 17 women) completed two 7-h laboratory visits separated by >7 days. Participants either remained seated for 7 h (SIT) or interrupted sitting with 3-min bouts of self-paced walking at 30-min intervals commencing 1 h after each meal (SIT-LESS). Physical activity, insulin regimen, experimental start times, and meal consumption were standardized during each arm. Plasma levels of interleukin (IL)-1β, tumour necrosis factor (TNF)-α, plasminogen activator inhibitor (PAI)-1 and fibrinogen were sampled at baseline, 3.5 and 7 h, and assessed for within- and between-group effects using a repeated measures ANOVA. The estimated glucose disposal rate was used to determine the insulin resistance status.

RESULTS

Vascular-inflammatory parameters were comparable between SIT and SIT-LESS at baseline (p > .05). TNF-α, IL-1β, PAI-1 and fibrinogen increased over time under SIT, whereas these rises were attenuated under SIT-LESS (p < .001). Specifically, over the 7 h under SIT, postprandial increases were detected in TNF-α, IL-1β, PAI-1 and fibrinogen (+67%, +49%, +49% and +62%, respectively; p < .001 for all). Conversely, the SIT-LESS group showed no change in IL-1β (-9%; p > .50), whereas reductions were observed in TNF-α, PAI-1 and fibrinogen (-22%, -42% and -44%, respectively; p < .001 for all). The intervention showed enhanced effects in insulin-resistant individuals with T1D.

CONCLUSIONS

Interrupting prolonged sitting with light-intensity activity ameliorates postprandial increases in vascular-inflammatory markers in T1D.

TRIAL REGISTRATION

The trial was prospectively registered (ISRCTN13641847).

Trends of physical activity and recreational screen time among Chinese children and adolescents: a national study from 2017 to 2019

BACKGROUND

The prevalence of physical inactivity and sedentary behavior among children and adolescents is a growing public health concern. This study aims to examine the trends in Physical Activity (PA) and Recreational Screen Time (RST) amongst children and adolescents in China, considering variations in genders, school levels, areas (urban versus rural), and regions (north versus south). The findings provide a foundation to guide policy and strategy making for future health promotion and development.

METHODS

An annual national cross-sectional survey was conducted in China from 2017 to 2019 cumulatively involving 52,503 (48% female) children and adolescents from grades 4 to 12 (aged 12.72 ± 2.12). Data on PA and RST were collected through self-administered questionnaires. Weighted least squares regression was used to analyze the trends and differences in PA and RST among the participants' profiles.

RESULTS

There was an annual decreased in PA compliance rate of approximately 3.43% (95% CI: 0.79-6.08%) for primary school students, primarily among males residing in rural areas, and in northern regions. Middle school students experienced a yearly decrease of about 5.23% (95% CI: 2.55-7.92%) in PA compliance across all genders, regions, and urban areas. Similarly, the RST compliance rates for primary school students declined by approximately 3.18% (95% CI: 1.57-4.78%) annually for all genders and areas, but only in the northern regions.

CONCLUSIONS

This research highlights a downward trend in PA and RST compliance amongst Chinese children and adolescents, with variations based on school level, gender, area, and region. Urgent policies and interventions are imperative to promote PA while mitigating excessive RST within these populations.

Co-construct, implement and evaluate a multi-level intervention to prevent a sedentary lifestyle in children-Study protocol of the CIPRES study

BACKGROUND

A sedentary lifestyle is commonly associated with a higher risk of chronic disease development. Among school-aged children from European countries, screen-time represents a significant portion of sedentary time with 39.8% of children spending more than 2h/day in front of a screen on average. Therefore, effective solutions to reduce sedentary behavior (SB) must be found. Multilevel interventions based on the socio-ecological model (SEM) are particularly relevant to take into account influences of the social environment on individuals' SB. Moreover, the trans-contextual model (TCM) can offer complementary levers for individuals' behavior change. The CIPRES study is a theory-based multilevel intervention designed to decrease the SB in French primary school children aged 8-10 years. The present paper describes the protocol of a randomized controlled study to evaluate the effectiveness of the CIPRES multilevel intervention on SB.

METHODS

The CIPRES study is a cluster-randomized controlled trial comparing intervention vs control groups. A total of 700 children are targeted for inclusion, distributed in four municipalities considered as clusters. The study consists of two successive phases: 1) co-building of a SB prevention intervention by using a participatory approach involving representatives of each level of the SEM (e.g., children, parents, staff from municipalities, teachers) and 2) implementation and evaluation of the intervention. The intervention will last for 6 weeks in each involved class. Primary outcome will be the sedentary time of children per week, assessed by accelerometry. In addition, children and their parents will be asked to fill out questionnaires concerning children's physical activity level, screen time, quality-of-life and variables of the TCM.

DISCUSSION

This study will give information on the effectiveness of a theory-based intervention, involving multiple levels of actors in the co-construction and the implementation of the intervention, that may interest schools and public health officers looking for innovative sedentary prevention programs.

Lifestyle, meal times, and sleep patterns changes in higher education professors during COVID-19: Association with non-communicable chronic diseases

BACKGROUND

In response to the COVID-19 pandemic, educational institutions had to swiftly adapt and transition to remote teaching in order to maintain academic activities. However, these changes presented a number of challenges for professors, which could have negative effects on their health.

OBJECTIVE

To analyze the association between changes in dietary and sleep habits, physical activity level, and sedentary behavior with the development of non-communicable diseases (NCDs) among Brazilian higher education professors during the pandemic period.

METHODS

This is a cross-sectional and retrospective study conducted using an online form. Generalized linear models, adjusted for age, sex, and body mass index, were used to verify the difference between pre-pandemic and pandemic periods. Logistic regression models were used to predict the odds ratio (OR) for the development of NCDs according to physical activity time, sedentary behavior time, dietary and sleep patterns.

RESULTS

A total of 936 professors residing across Brazil participated in the survey. The duration of sedentary behavior increased, sleep duration slightly decreased, and meal times shifted to earlier during the pandemic. A total of 22.9%of the participants reported the diagnosis of some NCDs during this period. Physical activity practice was associated with a lower risk of diseases during the pandemic, regardless of the intensity performed. On the other hand, late eating habits and excessive food consumption during the pandemic were associated with a higher risk.

CONCLUSION

The results provide data that can help in the development of public policies that promote health actions to minimize the consequences associated with the pandemic period.

Loneliness predicts decreased physical activity in widowed but not married or unmarried individuals

Background

Physical activity is associated with improved health and function in older adults, yet most older adults are sedentary. Loneliness is associated with decreased physical activity at the cross-section, but longitudinal studies are scarce. We examined longitudinal associations between loneliness and physical activity-and whether they were modified by marital status and network size (the number of children, relatives, and friends a person interacts with at least once a month).

Methods

We analyzed data from 1,931 older adults without dementia at baseline from the Rush Memory and Aging Project with a mean follow-up of 4.8 years (mean age 79.6 ± 7.7, 74.9% women). Loneliness was assessed using the de Jong Gierveld Loneliness Scale. Physical activity was assessed as the frequency with which participants engaged in five categories of activities (e.g., walking, gardening, calisthenics, bicycling, and swimming). Linear mixed effects models examined associations between baseline loneliness and change in physical activity over time after adjusting for demographics, depressive symptoms, global cognition, disability, network size, marital status, social support, and social and cognitive activities. We assessed for effect modification by marital status and network size.

Results

Associations between loneliness and physical activity differed by marital status. In widowed individuals, baseline loneliness was associated with a 0.06 h/week greater decrease in physical activity per year compared to those who were not lonely (p = 0.005, CI -0.1, 0.02)-which equaled a 150% decrease in physical activity per year. Loneliness did not predict a statistically significant decrease in physical activity in married or unmarried individuals.

Discussion

Loneliness is associated with decreased physical activity in widowed older adults and should be considered in the design of interventions to prevent or slow the decline in physical activity and promote healthy aging.

Impaired muscle oxygenation despite normal pulmonary function in type 2 diabetes without complications

Long-term hyperglycemia in individuals with type 2 diabetes (T2D) can detrimentally impact pulmonary function and muscle oxygenation. As a result, these factors can impede the body's adaptation to physical exertion. We aimed to evaluate the oxygen pathway during maximal exercise among overweight/obese individuals with type 2 diabetes free from complications, in comparison with a group of matched overweight/obese individuals without diabetes, specifically concentrating on the effects on pulmonary function and muscle oxygenation. Fifteen overweight/obese adults with type 2 diabetes [glycated hemoglobin (HbA1c) = 8.3 ± 1.2%] and 15 matched overweight/obese adults without diabetes underwent pre- and post exercise lung function assessment. A maximal incremental exercise test was conducted, monitoring muscle oxygenation using near-infrared spectroscopy and collecting arterial blood gas samples. Both groups exhibited normal lung volumes at rest and after exercise. Spirometric lung function did not significantly differ pre- and post exercise in either group. During maximal exercise, the type 2 diabetes group showed significantly lower augmentation in total hemoglobin and deoxygenated hemoglobin compared with the control group. Despite comparable usual physical activity levels and comparable heart rates at exhaustion, the type 2 diabetes group had a lower peak oxygen consumption than controls. No significant differences were found in arterial blood gas analyses ([Formula: see text], [Formula: see text], [Formula: see text], and [Formula: see text]) between the groups. Individuals with type 2 diabetes free from complications displayed normal pulmonary function at rest and post exercise. However, impaired skeletal muscle oxygenation during exercise, resulting from reduced limb blood volume and altered muscle deoxygenation, may contribute to the lower V̇o2peak observed in this population.NEW & NOTEWORTHY Individuals with type 2 diabetes free from micro- and macrovascular complications have normal resting pulmonary function, but their V̇o2peak is impaired due to poor skeletal muscle oxygenation during exercise. Tailoring exercise regimes for this population should prioritize interventions aimed at enhancing muscle oxygenation and blood flow improvement.

Levels of sedentary behaviour in people with fibromyalgia: a systematic review and meta-analysis

PURPOSE

Sedentary behaviour is associated with pain, fatigue, and a more severe impact of the disease in fibromyalgia, independently of physical activity levels. Despite this knowledge, little attention has been attributed to estimate sedentary behaviour in this population. The aims of this meta-analysis were to: (a) establish the pooled mean time spent sedentary, (b) investigate moderators of sedentary levels, and (c) explore differences with age- and gender-matched general population controls in people with fibromyalgia (PwF).

METHODS

Two independent authors searched major databases until 1 December 2022. A random effects meta-analysis was performed. The methodological quality of included studies was assessed with the Quality Assessment Tool for Observational Cohort and Cross-sectional Studies.

RESULTS

Across 7 cross-sectional studies of fair methodological quality, there were 1500 patients with fibromyalgia (age range = 43-53 years). PwF spent 545.6 min/day (95% CI = 523.7-567.5, p < 0.001, N = 3) engaging in sedentary behaviour. Self-reported questionnaires overestimate sedentary levels with 314.3 min/day (95% CI = 302.0-326.6, p = 0.001, N = 2). PwF spent 36.14 min/day (95% CI = 16.3-55.9, p < 0.001) more in sedentary behaviour than general population controls.

CONCLUSIONS

PwF are more sedentary than the general population. The limited available data should however be considered with caution due to substantial heterogeneity.

Effectiveness of interventions on sedentary behaviors in office workers: a systematic review and meta-analysis

OBJECTIVES

Various interventions have sought to break sedentariness among office workers, but their pooled effect on sitting time reduction remains unknown. Also, it is essential to compare the effectiveness of different intervention types.

STUDY DESIGN

Systematic review and meta-analysis.

METHODS

A literature search was conducted in the PubMed, EMBASE, Scopus, Web of Science, MEDLINE (via EBSCO), PsycINFO, and Cochrane Library databases from inception to May 2, 2023. Two independent reviewers screened eligibility, extracted data, and assessed the risk of bias using the Cochrane risk of bias tool 2.0. Randomized controlled trials aiming to reduce sitting at work were included. The primary outcome was sitting time at work per day. The secondary outcomes included cardiometabolic risk factors, psychological well-being, and work engagement. A random effects model was performed to synthesize continuous data as mean differences with 95% confidence intervals (95% CIs).

RESULTS

Twenty-four studies with 3169 participants were included. All intervention types in combination significantly reduced workplace sitting by 38 min per workday (95% CI: -47.32 to -28.72; P < 0.001; I2 = 49.78%). Interventions using environmental support (ES), motivational strategies (MS), or multiple components (multi) had all shown a significant reduction in work-time sedentary behavior (SB) relative to control groups. Regarding secondary outcomes, no significant effects were observed in physical or psychological outcomes besides high-density lipoprotein.

CONCLUSIONS

Findings suggest that SB reduction interventions are generally effective for reducing workplace sitting. Multi interventions with both ES and MS are recommended for future clinical applications. Future studies should aim not only to reduce SB but also to attain the benefits of SB reduction interventions on physical and psychological well-being.

The association between health behaviours and academic performance moderated by trait mindfulness amongst university students: an observational study

Objectives

To target health communication at less health-conscious groups, evidence on health behaviours' effects on non-health-related outcomes - such as academic performance - is necessary. Recent research has highlighted the associations of various health behaviours on academic performance of university students. However, there is a lack of research investigating the most predominant health behaviours simultaneously and their association with academic performance, as well as the factors that potentially influence the direction or strength of these associations. Therefore, this study investigated (I) which of the predominant health behaviours (physical activity, healthy diet, sleep, sedentary behaviour, alcohol consumption, smoking, drug use) are most associated with academic performance and (II) whether the personal resource of trait mindfulness moderates these associations.

Methods

An online survey was conducted amongst university students during the 2021 summer semester. Group differences in academic performance regarding health behaviours were analysed using ANOVA (N = 1,049). A first linear regression model (N = 571), considering all selected health behaviours simultaneously, assessed their association with academic performance. A second model (N = 540) assessed interaction effects of health behaviours and trait mindfulness. Separate regressions assessed each interaction's association with academic performance.

Results

Sleep, fruit and vegetable consumption, and gender were significantly associated with academic performance. The second model showed no significant interaction effects.

Conclusion

Targeting sleep and fruit and vegetable consumption might be the most promising strategies for elevating students' academic performance, thereby enabling health communication strategies to reach groups driven by performance improvements rather than health benefits.

Sedentary behavior does not predict low BMD nor fracture-population-based Canadian Multicentre Osteoporosis Study

Sedentary behavior (SB) or sitting is associated with multiple unfavorable health outcomes. Bone tissue responds to imposed gravitational and muscular strain with there being some evidence suggesting a causal link between SB and poor bone health. However, there are no population-based data on the longitudinal relationship between SB, bone change, and incidence of fragility fractures. This study aimed to examine the associations of sitting/SB (defined as daily sitting time), areal BMD (by DXA), and incident low trauma (fragility) osteoporotic fractures (excluding hands, feet, face, and head). We measured baseline (1995-7) and 10-yr self-reported SB, femoral neck (FN), total hip (TH), and lumbar spine (L1-L4) BMD in 5708 women and 2564 men aged 25 to 80+ yr from the population-based, nationwide, 9-center Canadian Multicentre Osteoporosis Study. Incident 10-yr fragility fracture data were obtained from 4624 participants; >80% of fractures were objectively confirmed by medical records or radiology reports. Vertebral fractures were confirmed by qualitative morphological methods. All analyses were stratified by sex. Multivariable regression models assessed SB-BMD relationships; Cox proportional models were fit for fracture risk. Models were adjusted for age, height, BMI, physical activity, and sex-specific covariates. Women in third/fourth quartiles had lower adjusted FN BMD versus women with the least SB (first quartile); women in the SB third quartile had lower adjusted TH BMD. Men in the SB third quartile had lower adjusted FN BMD than those in SB first quartile. Neither baseline nor stable 10-yr SB was related to BMD change nor to incident fragility fractures. Increased sitting (SB) in this large, population-based cohort was associated with lower baseline FN BMD. Stable SB was not associated with 10-yr BMD loss nor increased fragility fracture. In conclusion, habitual adult SB was not associated with subsequent loss of BMD nor increased risk of fracture.

Association of daily sitting time and coffee consumption with the risk of all-cause and cardiovascular disease mortality among US adults

BACKGROUND

Sedentary behavior has been demonstrated to be a modifiable factor for several chronic diseases, while coffee consumption is believed to be beneficial for health. However, the joint associations of daily sitting time and coffee consumption with mortality remains poorly understood. This study aimed to evaluate the independent and joint associations of daily sitting time and coffee intakes with mortality from all-cause and cardiovascular disease (CVD) among US adults.

METHODS

An analysis of a prospective cohort from the 2007-2018 National Health and Nutrition Examination Survey of US adults (n = 10,639). Data on mortality were compiled from interview and physical examination data until December 31, 2019. Daily sitting time was self-reported. Coffee beverages were from the 24-hour diet recall interview. The main outcomes of the study were all-cause and cardiovascular disease mortality. The adjusted hazard ratios [HRs] and 95% confidence intervals [CI] were imputed by Cox proportional hazards regression.

RESULTS

Among 10,639 participants in the study cohort, there were 945 deaths, 284 of whom died of CVD during the follow-up period of up to 13 years. Multivariable models showed that sitting more than 8 h/d was associated with higher risks of all-cause (HR, 1.46; 95% CI, 1.17-1.81) and CVD (HR, 1.79; 95% CI, 1.21-2.66) mortality, compared with those sitting for less than 4 h/d. People with the highest quartile of coffee consumption were observed for the reduced risks of both all-cause (HR, 0.67; 95% CI, 0.54-0.84) and CVD (HR, 0.46; 95% CI, 0.30-0.69) mortality compared with non-coffee consumers. Notably, joint analyses firstly showed that non-coffee drinkers who sat six hours or more per day were 1.58 (95% CI, 1.25-1.99) times more likely to die of all causes than coffee drinkers sitting for less than six hours per day, indicating that the association of sedentary with increased mortality was only observed among adults with no coffee consumption but not among those who had coffee intake.

CONCLUSIONS

This study identified that sedentary behavior for more than 6 h/d accompanied with non-coffee consumption, were strongly associated with the increased risk of mortality from all-cause and CVD.

Interrupting sitting acutely attenuates cardiometabolic risk markers in South Asian adults living with overweight and obesity

PURPOSE

This study examined the acute effects of interrupting sitting with light-intensity walking on postprandial cardiometabolic risk markers in South Asian adults.

METHODS

South Asians with overweight/obesity (n = 19; body mass index [BMI] > 23 kg·m-2) and normal-weight (n = 8; BMI 18.0-22.9 kg·m-2) aged 48.8 ± 5.6 years completed two, 5-h conditions: (1) prolonged sitting (SIT), and (2) interrupted sitting with 5-min bouts of light-intensity walking every 30-min (INT-SIT). Blood samples and resting expired air samples were collected throughout each condition. Statistical analyses were completed using linear mixed models.

RESULTS

In participants with overweight/obesity, postprandial glucose, triglycerides (TAG) and metabolic load index (MLI) over time were lower, whereas resting substrate utilisation and resting energy expenditure (REE) were higher, in INT-SIT than SIT (all p ≤ 0.05). Compared with SIT (0.18 [95% CI 0.13, 0.22] kcal.min-1), INT-SIT (0.23 [95% CI 0.18, 0.27] kcal.min-1) increased postprandial REE iAUC in participants with overweight/obesity (p = 0.04, d = 0.51). Postprandial TAG concentrations over time were lower in INT-SIT versus SIT (p = 0.01, d = 30) in normal-weight participants, with no differences in any other outcomes for this sample group.

CONCLUSION

These findings suggest that interrupting sitting with 5-min bouts of light walking every 30-min acutely attenuates cardiometabolic risk markers among South Asians living with overweight/obesity, whereas limited effects may be seen in individuals with normal-weight.

[Encouragement of adapted physical activity for three months after the end of treatment in patients with head and neck cancer: A pre-post interventional study]

CONTEXT

In our institution, patients with upper aero-digestive tract cancer receive adapted physical activity (APA) awareness training as part of their holistic oncology care program. The main aim of this study was to show that raising awareness of APA helped to increase self-reported PA levels, as assessed by questionnaire.

METHOD

This retrospective study included 67 patients with localized Head and Neck cancer. The intervention consisted of an APA teacher; a face-to-face consultation before the start of oncological treatment, four monthly telephone interventions in the three months following the end of treatment. The pre-post evaluation focused on self-reported APA practices before and three months after the end of oncology treatment.

RESULTS

APA awareness training significantly increased average total PA, average moderate PA intensity, average weekly walking frequency, average walking intensity, and significantly reduced daily sitting time. The search for correlations between body composition or type of treatments and changes in PA levels showed no significant results.

CONCLUSION

This study showed that a basic APA awareness training integrated into a holistic oncology care program could increase patients' self-reported PA levels. The next step will be to verify the objectivity of the increase in self-reported PA, and then to assess its effect on quality of life and survival.

Comparison of Physical Activity and Sedentary Behavior between Work in Office and Work From Home: A Self-controlled Study

OBJECTIVE

To compare physical activity levels and sedentary behavior between individuals working in the office and those working from home, with the aim of elucidating the potential implications on employees' health.

METHODS

We used triaxial accelerometers to assess the physical activity levels of 94 white-collar employees from a large-scale manufacturing company in Japan. They were instructed to wear the accelerometers during their working hours, which included the commuting time on work-in-office days.

RESULTS

The mean energy expenditure on work in office was 426 kcal for individuals, while it was 228 kcal on work from home (P < 0.01). In addition, not including commuting, the time spent sedentary on work-from-home days was higher than that on work-in-office days by 20 minutes.

CONCLUSIONS

Work from home decreases physical activity and increases sedentary time compared with work in office.

Daily time spent on screens and psychological well-being: Cross-sectional association within the SUN cohort

BACKGROUND

The impact of various lifestyles on psychological well-being (PWB) remains under-studied. We aimed to explore the cross-sectional association between daily screen use (television, tablet and mobile phone) and PWB within the SUN cohort.

METHODS

PWB was assessed using the 29-item Ryff scale (ranging from 29 to 174), and participants with scores >75th percentile were considered as having optimal PWB. Participants were categorized based on their self-reported weekly screen usage hours. Postestimation logistic regression models assessing the prevalence likelihood of not achieving optimal PWB were adjusted for sociodemographic, psychological, personality and lifestyles factors. Isotemporal substitution models explored the potential impact on PWB resulting from replacing 1 h/day of screen time with 1 h/day of exercise.

RESULTS

The study included 3051 participants (55.8% women, mean age 57.3 ± 11.1 years, mean Ryff's score: 139.1 ± 17.4 points). Daily screen use for ≥2 h was associated with a higher prevalence likelihood of not achieving an optimal PWB (Prevalence Ratio [PR]:1.09; 95% CI:1.01-1.18). Among PWB dimensions, screen use ≥2 h/day was linked to an increased likelihood of not achieving optimal scores in environmental mastery (PR:1.11; 95% CI:1.02-1.20), life purpose (PR:1.10; 95% CI:1.02-1.18), and personal growth (PR:1.09; 95% CI:1.01-1.18). Replacing 1 h of daily screens time with 1 h of exercise may lead to potential improvements in environmental mastery (Odds Ratio [OR]:0.87; 95% CI:0.76-0.99), purpose in life (OR:0.86; 95% CI: 0.76-0.98), personal growth (OR:0.84; 95% CI:0.73-0.96) and positive interpersonal relationships (OR:0.86; 95% CI:0.75-0.99).

CONCLUSIONS

These findings highlight the importance of reducing screen use activities and increasing physical exercise for achieving optimal PWB.

[Evolution of sedentarism prevalence in Spanish population between 1987 and 2020]

BACKGROUND AND OBJECTIVE

Sedentary behavior is a predictive factor for numerous diseases. The objective of this study was to assess the evolution of the prevalence of sedentary behavior in the Spanish adult population between 1987 and 2020.

METHODS

The data sources were the National and European Health Surveys. The prevalence of sedentary behavior was assessed in three scenarios (main activity, leisure time and all scenarios). Prevalence of sedentary behavior was estimated overall, by sex and age group. In all scenarios, prevalence was also estimated by Autonomous Community. The prevalence trend was analyzed with the annual percent change (APC) obtained through joinpoint models.

RESULTS

The prevalence of sedentary in the main activity ranged from 31.2% in 1987 to 38.4% in 2020 [PCA: 0.7 (0.5-1.0)], being higher in men than in women and higher in younger and older people. The prevalence of sedentary in the leisure time varied between 55.1% in 1993 and 36.4% in 2020 [PCA: -1.4 (-1.9 to -0.9)], being always higher in women, higher in those over 64 years of age and lower in those aged 16-24 years. Cantabria and the Canary Islands were the Autonomous Communities with the lowest prevalence of sedentary behavior in all scenarios.

CONCLUSIONS

The prevalence of sedentary behavior in the main activity is increasing in Spain, whereas during leisure time it is decreasing. It is important to implement prevention and health promotion measures aimed at reducing sedentary behavior in the population.

Study protocol and rationale of "the UP project": evaluating the effectiveness of active breaks on health indicators in desk-based workers

Background

Excessive sedentary time has been negatively associated with several health outcomes, and physical activity alone does not seem to fully counteract these consequences. This panorama emphasizes the essential of sedentary time interruption programs. "The Up Project" seeks to assess the effectiveness of two interventions, one incorporating active breaks led by a professional and the other utilizing a computer application (self-led), of both equivalent duration and intensity. These interventions will be compared with a control group to evaluate their impact on physical activity levels, sedentary time, stress perception, occupational pain, and cardiometabolic risk factors among office workers.

Methods

This quasi-experimental study includes 60 desk-based workers from universities and educational institutes in Valparaiso, Chile, assigned to three groups: (a) booster breaks led by professionals, (b) computer prompts that are unled, and (c) a control group. The intervention protocol for both experimental groups will last 12 weeks (only weekdays). The following measurements will be performed at baseline and post-intervention: cardiometabolic risk based on body composition (fat mass, fat-free mass, and bone mass evaluated by DXA), waist circumference, blood pressure, resting heart rate, and handgrip strength. Physical activity and sedentary time will be self-reported and device-based assessed using accelerometry. Questionnaires will be used to determine the perception of stress and occupational pain.

Discussion

Governments worldwide are addressing health issues associated with sedentary behavior, particularly concerning individuals highly exposed to it, such as desk-based workers. Despite implementing certain strategies, there remains a noticeable gap in comprehensive research comparing diverse protocols. For instance, studies that contrast the outcomes of interventions led by professionals with those prompted by computers are scarce. This ongoing project is expected to contribute to evidence-based interventions targeting reduced perceived stress levels and enhancing desk-based employees' mental and physical well-being. The implications of these findings could have the capacity to lay the groundwork for future public health initiatives and government-funded programs.

Association between circadian physical activity trajectories and incident type 2 diabetes in the UK Biobank

Physical activity (PA) is linked to a decreased risk of type 2 diabetes mellitus (T2DM). However, the influence of circadian PA trajectories remains uncertain. This study aims to explore the optimal circadian PA trajectory pattern for reducing the risk of T2DM. Methods: A total of 502,400 participants were recruited from the UK Biobank between 2006 and 2010, and 102,323 participants provided valid accelerometer-captured acceleration data. After excluding individuals with prior T2DM, 99,532 participants were included in the final analysis. We initially investigated the association between PA intensity at 24 hourly time points and T2DM. Subsequently, PA trajectories were identified using K-means cluster analysis. Cox proportional hazard models were employed to estimate hazard ratios (HR). Four distinct PA trajectories were identified: consistently low, single peak, double peak, and intense trajectories. Compared to consistently low, single peak, double peak and intense PA trajectory reduced the risk of T2DM progressively. Sensitivity analyses, further excluding individuals with glycated hemoglobin (HbA1c) ≥ 6.5% or random glucose ≥ 11.1 mmol/L and adjusted for daily average acceleration, yielded consistent results. This confirms that the ideal circadian PA trajectory serves as a protective factor, independently of PA intensity. Subgroup analyses indicated that these effects were more pronounced in men and individuals with eGFR < 60 mL/(min*1.73 m2). In conclusion, ideal circadian PA trajectory patterns (especially intense and then double peak) reduced risk of T2DM.

Physical Activity and Sedentary Behavior as Treatable Traits for Clinical Control in Moderate-to-Severe Asthma

BACKGROUND

Physical activity and sedentary behavior are treatable traits that may impact asthma control in distinct manners, but this impact remains poorly understood.

OBJECTIVE

To evaluate the influence of physical activity and sedentary behavior on clinical control in adults with moderate-to-severe asthma.

METHODS

This cross-sectional, multicentric study included 426 individuals with moderate-to-severe asthma. Assessments included physical activity and sedentary time (actigraphy), clinical asthma control (Asthma Control Questionnaire [ACQ]), quality of life (Asthma Quality of Life Questionnaire), anxiety and depression symptoms (Hospital Anxiety and Depression Scale), anthropometric data, and lung function. Participants were grouped according to physical activity levels and sedentary behavior.

RESULTS

Participants who walked ≥7500 steps/day presented better ACQ scores than those who walked <7500 steps/day (P < .05), independent of sedentary status. The percentage of patients with controlled asthma was higher in the active/sedentary (43.9%) and active/nonsedentary (43.8%) groups than in the inactive/sedentary (25.4%) and inactive/nonsedentary (23.9%) groups (P < .02). The likelihood of having uncontrolled asthma according to the treatable traits of physical inactivity (odds ratio [95% confidence interval]: 2.36 [1.55-3.59]), higher anxiety (2.26 [1.49-3.42]), and depression symptoms (1.95 [1.28-2.95]) was significant (P ≤ .002). Obesity and sedentary time were not associated with asthma control.

CONCLUSIONS

Our results show that ≥7500 steps/day is associated with better asthma control independent of sedentary time in adults with moderate-to-severe asthma. Physical inactivity, anxiety, and depression symptoms are associated with higher odds of uncontrolled asthma. These results suggest that interventions should mainly focus on increasing physical activity rather than reducing sedentary time.

Ideal 24-h physical activity trajectory reduces all-cause, cause-specific mortality and cardiovascular outcomes through aging deceleration and inflammation regulation: A UK biobank study

BACKGROUND

Physical activity (PA) is associated with mortality and cardiovascular disease (CVD). However, the effect of circadian PA trajectories remains ambiguous. This study aimed to explore ideal circadian PA patterns to reduce mortality and CVD, and potential mediators.

METHODS

502,400 participants from UK Biobank were recruited between 2006 and 2010. Among them, 102,323 participants got valid continuously capturing acceleration data over 7 days by wrist-worn accelerometer. K-means cluster analysis was used to identify PA trajectories. The associations of PA with all-cause, cause-specific mortality and CVD were assessed by cox regression. A sensitivity test was also conducted, starting from the time of acceleration collection and excluding participants with corresponding disease prior to it. Furthermore, the mediation of aging and inflammation were explored.

RESULTS

During a median follow-up of 12.9 years, 3482 deaths were recorded (704 were due to CVD). Five distinct PA trajectories were identified: Persistently Low, Moderate and Stable, Single Increase, Double Increase, and Vigorous patterns. Ideal PA trajectory patterns offered progressively protective benefits against all-cause, CVD caused mortality and CVD, especially in Double Increase and Vigorous patterns. Other cause-specific mortality and renal failure incidence showed similar trend. The sensitivity result was consistent. The mediating effects of phenotypic age and inflammation markers were statistically significant.

CONCLUSION

Ideal PA trajectories offered protective benefits against all-cause, cause-specific mortality and CVD. The protection was associated with both intensity and circadian distribution. Double Increase and Vigorous activity patterns decreased these risks more significantly. Crucially, this protection was mediated by aging deceleration and inflammation regulation.

Quantifying the time-varying association between objectively measured physical activity and mortality in US older adults over a 12-year follow-up period: the NHANES 2003-2006 study

Objectively measuring physical activity (PA) has consistently shown an association with reduced all-cause mortality risk in cross-sectional studies. However, the strength of this association may change over time. We quantify the time-varying, covariate-adjusted association between the total volume of PA and all-cause mortality over a 12-year follow-up period using Cox regression with a time varying effect of population-referenced quantile total activity count adjusted for traditional risk factors. Analyses focus on participants 50-84 years old with adequate accelerometer wear time and without missing covariates. The findings suggest that (1) the use of baseline PA in Cox models with long follow-up periods may be inappropriate without time-varying effects and (2) the use of accelerometry derived volume of PA in risk score calculations may be most appropriate for short-term to medium-term risk scores.