OBJECTIVE: 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.

BACKGROUND: This study aimed to investigate the relationships between accelerometer-measured physical activity (PA) and sedentary behaviour (SB) with physical function (PF) among older Chinese women in the community.
METHODS: The present study comprised 1,113 community-dwelling older females, with an average age of 65 ± 2 years. We employed a linear regression analysis to investigate the relationship between patterns of PA and SB with PF. PA variables consisted of total PA time, bouted PA time (a continuous PA that lasts equal to or more than 10 min), and sporadic PA time (a continuous PA that lasts less than 10 min). SB variables included total SB time, 30-min bout of SB (a continuous SB that lasts equal to or more than 30 min), and 60-min bout of SB (a continuous SB that lasts equal to or more than 60 min). PF variables comprised handgrip strength (HGS), one-legged stance test with eyes closed (OLSTEC), usual walking speed (UWS), maximum walking speed (MWS) and chair-stand time (CT). To explore the joint effects of moderate-to-vigorous-intensity PA (MVPA) and SB on PF, we divided the duration of SB and MVPA participation in older women into different combinations: low MVPA & high SB, low MVPA & low SB, high MVPA & high SB, high MVPA & low SB.
RESULTS: The study revealed a significant association between 30-min bout of SB and CT, which remained after adjusting for total MVPA time (P = 0.021). Both total MVPA and bouted MVPA were found to be positively associated with better UWS, MWS, CT, and PF Z-score. When the combination of low MVPA & high SB was used as a reference, the regression coefficients for PF ascended by 1.32 (P < 0.001) in the high MVPA & high SB group and by 1.13 (P < 0.001) in the high MVPA & low SB group.
CONCLUSIONS: A significant association was observed between poorer lower limb function and prolonged, uninterrupted SB in older women, rather than with the total SB time. Concurrently, the insufficient engagement in MVPA may also be a crucial factor contributing to poorer PF in older women. Engaging in longer durations and higher intensity of PA, such as bouts of MVPA lasting a minimum of 10 min or longer, may contribute to better PF.

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.

UNASSIGNED: There is limited information about the relationship between physical activity (PA) and sedentary behaviors in chronic kidney disease (CKD). Therefore, this study aims to explore the associations of accelerometer-measured PA and sedentary behaviors with CKD.
UNASSIGNED: A cross-sectional study was conducted using data from the National Health and Nutrition Examination Survey in the 2003-2004 and 2005-2006 survey cycles. A uniaxial accelerometer measured physical activity (PA) and sedentary time (ST). The associations of PA and ST with estimated glomerular filtration rate (eGFR) and odds of CKD adopted the generalized linear regression, multivariable logistic regression, and isotemporal substitution models.
UNASSIGNED: A total of 5,990 adults with 605 CKD patients were included in this study. Compared with the individuals in the first quartile group, participants in the fourth quartile of low-intensity physical activity (LIPA), moderate to vigorous physical activity (MVPA), and ST were associated with 52% (35%, 65%) and 42% (14%, 62%) lower odds of CKD and 64% (17%, 131%) higher odds of CKD, respectively. Substituting 30 min/day of ST with equivalent LIPA/MVPA contributed to risk reduction in CKD.
UNASSIGNED: The findings suggest that increased LIPA and MVPA and reduced ST were associated with a lower risk of CKD and that replacing ST with LIPA may decrease the risk of CKD.

BACKGROUND: Childhood obesity is increasingly recognized as a major public health challenge worldwide, and excessive sedentary screen time is emerging as a key risk factor. This study aimed to assess the recreational screen sedentary time of Chinese primary school-aged children and investigate the relationship between screen-related family factors and the outcome variable.
METHODS: Our study used data from a cross-sectional survey collected from fifth-grade students and their parents in Beijing, China, from April to May 2018 (n = 2,373). The questions included basic demographic information, family socioeconomic status, students\' and parents\' sedentary and exercising habits, within-family communicational factors, and health belief patterns. The recreational screen sedentary time of the children was compared across demographic groups. The study employed multivariate linear regression models to examine associations between children\'s screen time and various family factors, as well as the moderating effect of overall family communication.
RESULTS: Our findings revealed an average daily recreational screen sedentary time of 2.4 h among participants. Screen time significantly varied across demographic categories, including children\'s sex, age, residence, parents\' education, household income, family size, and primary family member. After adjustment, the proportion of child-owned digital devices (p < 0.01), child\'s personal room (p < 0.05), family screen-viewing together (p < 0.01), and parental screen time (p < 0.01) were positively related to children\'s recreational sedentary screen time. Parental restrictions on screen time (p < 0.001) and attitudes toward reducing sitting time (p < 0.01) were correlated with a decrease in children\'s screen time. The overall family communication environment significantly moderated the effects of parental practice of restricting children\'s screen time (p < 0.001), positive reinforcement by parents (p < 0.05), and parents\' recreational sedentary screen time (p < 0.001).
CONCLUSIONS: Our findings underscored the significance of family dynamics, parental practices, and communication in shaping children\'s screen time behaviors, providing valuable insights for tailored interventions and strategies to reduce childhood obesity.

Previous studies have reported an association between physical activity and the occurrence and progression of knee osteoarthritis (KOA). However, the existing evidence remains limited and of low-quality. This study aimed to examine the causal relationship between different levels of physical activity and KOA. Instrumental variables, represented by single nucleotide polymorphisms (SNPs), were utilized to capture sedentary behavior, appropriate physical exercise, and excessive physical activity. Aggregated statistics from the UK Biobank genome-wide association study dataset were used to assess the impact of these SNPs on KOA. Causality was estimated using inverse variance weighting (IVW), MR Egger, simple model, weighted median, and weighted model approaches. The stability of the results was assessed through heterogeneity and sensitivity analyses. Mendelian randomization (MR) analysis revealed a strong association between sedentary behavior and KOA, with an odds ratio (OR) of 2.096 (95% CI: 1.506-2.917) and a P value of 1.14 × 10-5. Appropriate physical exercise behavior exhibited a strong negative association with KOA, with an OR of 0.147 (95% CI: 0.037-0.582) and a P value of 0.006. Conversely, excessive physical activity behavior showed a significant positive association with KOA, with an OR of 2.162 (95% CI: 1.327-3.521) and a P value of .002. Our findings indicate that sedentary behavior and excessive physical activity are identified as risk factors for KOA, whereas engaging in appropriate physical exercise emerges as a protective factor against the development of KOA.

BACKGROUND: Insufficient physical activity (PA) is a major risk factor for non-communicable diseases (NCDs) and one of the leading causes of premature mortality worldwide. This study examined the prevalence and independent determinants of insufficient PA among adults resident of Tehran utilizing Tehran Cohort Study Data (TeCS).
METHODS: We used the recruitment phase data from the TeCS with complete data on PA. PA was assessed through a Likert-scaled question and categorized into three groups. Utilizing data from the 2016 national census, the age- and sex-weighted prevalence of insufficient PA in Tehran was determined. The adjusted logistic regression model is used to neutralize influencing factors and determine the factors associated with insufficient PA.
RESULTS: The weighted prevalence of insufficient PA was 16.9% among the 8213 adult citizens of Tehran, with a greater prevalence among females (19.0% vs. 14.8% among males). Additionally, older age groups, unemployed, housewives, and illiterate educated participants displayed a much higher prevalence of insufficient PA (p < 0.001). Moreover, Tehran\'s central and southern districts had higher rates of insufficient PA. Concerning the adjusted regression model, older age (Odds ratio [OR]: 4.26, 95% confidence interval [95% CI]: 3.24-5.60, p < 0.001), a lower education level (p < 0.001), unemployment (OR: 1.80, 95% CI: 1.28-2.55, p = 0.001), being a housewife (OR: 1.44, 95% CI: 1.15-1.80, p = 0.002), higher body mass index (BMI) (OR for BMI > 30: 1.85, 95% CI: 1.56-2.18, p < 0.001), opium consumption (OR: 1.92, 95% CI: 1.46-2.52, p < 0.001), diabetes mellitus (OR: 1.25, 95% CI: 1.06-1.48, p = 0.008), hypertension (OR: 1.29, 95% CI: 1.11-1.50, p = 0.001), and coronary artery diseases (OR: 1.30, 95% CI: 1.05-1.61, p = 0.018), were significantly associated with insufficient PA.
CONCLUSIONS: The identified associated factors serve as a valuable guide for policymakers in developing tailored intervention strategies to address the needs of high-risk populations, particularly among older adults and females.

Canadian movement guidelines focused on physical activity (PA), sleep, and screen time support childhood development and reduce the risk of chronic disease. Accelerometers are often used to capture these behaviors; however, they are limited in their ability to record daytime sleep due to potential misclassification.
OBJECTIVE: The objectives of this study were to 1) determine the prevalence of children enrolled in the Guelph Family Health Study who met the guidelines and to 2) compare the impact of different sleep measurement methods.
METHODS: Toddlers (1.5-<3 years; n = 128; valid data for all movement behaviors, n = 70), preschoolers (3-<5 years; n = 143; valid data for all movement behaviors, n = 104), and school-aged (5-<6 years; n = 49; valid data for all movement behaviors, n = 31) children were included. Screen time and sleep habits were obtained through parental report and published normative data. PA and sleep were recorded using accelerometers (wGT3X-BT ActiGraph; right hip).
RESULTS: It was found that 66 % of toddler, 44 % of preschool, and 63 % of school-aged children met the screen time guidelines. Further, 63 % of toddler, 98 % of preschooler, and 80 % of school-aged children met PA guidelines. Sleep guideline compliance ranged from 3 % to 83 % in toddler, 27 % to 92 % in preschooler, and 32 % to 90 % in school-aged children. These proportions were found to be significantly different (Cochran\'s Q and McNemar\'s tests).
CONCLUSIONS: Nearly all children met PA guidelines. In contrast, less than half to two-thirds met screen time guidelines. Compliance with sleep guidelines varied substantially with measurement method, highlighting the need for standardization.

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

Effects of parent-child dyad interventions on behavior remain unclear. This randomized controlled trial investigated if, compared with a control condition, three types of physical activity (PA) planning interventions (individual \"I-for-me,\" dyadic \"we-for-me,\" and collaborative \"we-for-us\") would reduce sedentary behavior (SB) time in parents and their children. The study involved 247 dyads comprising parents (aged 29-66) and their children (aged 9-15), randomized into one of the three types of PA planning-intervention arms or the control condition. Mixed models were applied to analyze data from a preregistered trial (NCT02713438) with the outcome of accelerometer-measured SB time, assessed at 1-week and 36-week follow-ups. Although children\'s SB remained unaffected by the planning interventions, a small reduction of SB time was found among parents in the collaborative (p = .048) and individual (p = .042) planning conditions. The effects were observed at the 1-week follow-up only. While short-term reductions in parents\' SB were achieved, these were not sustained long-term. PA planning interventions delivered to parent-child dyads did not substantially reduce children\'s SB, which may be due to young people\'s needs of increased independence from their parents.