Resistance training presents beneficial effects on bone development of adolescents engaged in swimming but not in impact sports: ABCD Growth Study.

BACKGROUND: Sports practice during adolescence is important to enhance bone development, although it may provide different effects depending on the mechanical impact present in the sport. Besides, resistance training (RT) may also induce bone changes directly (via muscle contractions) and indirectly (via myokines). However, there have been no studies analyzing the longitudinal influence of engaging in sport with and without added mechanical load. Thus, this study aims to analyze the combined effects of sports participation and resistance training on areal bone mineral density (aBMD) accrual in adolescent athletes participating in swimming and impact sports for 12-months. METHODS: This was a 12-month longitudinal study. The sample comprised 91 adolescents (21 females) aged 10 to 18 years, engaged in impact sports (basketball, tennis, track & field, baseball and gymnastics, n = 66) and non-impact sport (swimming, n = 25). The sample was divided according to resistance training participation: impact sports only (n = 45), impact sports + resistance training (n = 21), swimming-only (n = 17) and swimming + resistance training (n = 8). aBMD and soft tissues were measured using dual-energy X-ray absorptiometry. Generalized linear models analysis was used for the resistance training (RT) x type of sport interaction in predicting aBMD changes overtime, adjusting for maturation, sex and baseline aBMD. RESULTS: After 12-months, all groups showed a significant increase in aBMD, except for the swimming groups (regardless of resistant training), which showed a significant loss in spine aBMD (-0.045 [-0.085 to -0.004] g/cm2 in swimming-only and - 0.047 [-0.073 to -0.021] g/cm2 in swimming + RT). In comparisons between groups, only swimming + RT group, compared with swimming-only group presented higher upper limbs aBMD (0.096 g/cm2 [0.074 to 0.118] in swimming + RT vs. 0.046 [0.032 to 0.060] g/cm2 in swimming only; p < 0.05) and whole body less head (WBLH) aBMD (0.039 [0.024 to 0.054] g/cm2 in swimming + RT vs. 0.017 [0.007 to 0.027] g/cm2 swimming-only; p < 0.05). CONCLUSION: Despite the significant gain in aBMD in all groups and body sites after 12-months, except for the spine site of swimmers, the results indicate that participation in RT seems to improve aBMD accrual in swimmers at the upper limbs and WBLH.

Active school commuting in adolescents from 28 countries across Africa, the Americas, and Asia: a temporal trends study.

BACKGROUND: Evidence examining trends in active school commuting among adolescents are mainly single-country studies, and principally focused on high-income countries. Thus, the present study aims to examine temporal trends in adolescents' active school commuting and to examine if there are differences in such trends by sex. We used nationally representative samples of 28 countries, which were predominantly low- and middle-income countries (LMICs), covering 5 different WHO regions. METHODS: Data from the Global School-based Student Health Survey 2004-2017 were analyzed in 177,616 adolescents [mean (SD) age: 13.7 (1.0) years; 50.7% girls]. Active school commuting was self-reported (frequency of walking or riding a bike to and from school in the past 7 days). The prevalence and 95%CI of active school commuting (i.e., ≥ 3 days/week) was calculated for the overall sample and by sex for each survey. Crude linear trends in active school commuting were assessed by linear regression models. Interaction analyses were conducted to examine differing trends among boys and girls. RESULTS: Trends in active school commuting were heterogeneous across countries, with results showing stable patterns for the majority (16/28), decreasing trends for some (7/28) and increasing trends over time for a few (5/28). The majority of countries showed no differences in active school commuting trends between girls and boys. CONCLUSIONS: The quantification of changes in adolescents' active school commuting over time, together with a deeper understanding of local determinants for such behaviors will provide valuable evidence to inform the development of tailored and context-specific actions.

Social isolation is associated with higher leisure-time sedentary behavior and lower physical activity practice: A multi-country analysis of data from 79 countries from the Global School-Based Student Health Survey.

AIM: To investigate the association of social isolation with physical activity and leisure-time sedentary behavior among adolescents. METHODS: We used data from the Global School-based Health Survey, including a representative sample of 296,861 adolescents (11-18y) from 79 countries (48.9% girls, 14.5 ± 1.6 years). Social isolation was estimated by combining the self-reported number of friends and loneliness perception. Physical activity and leisure-time sedentary behavior were assessed through questionnaires. Multinomial logistic regression models were created to analyze the associations of social isolation with physical activity and leisure-time sedentary behavior. RESULTS: Compared with those practicing ≥60 min of physical activity during 1-4 days/week, social isolation was associated with a higher prevalence of not practicing physical activity (Prevalence ratio [PR]:1.24; 95%CI:1.19-1.29), and a lower prevalence of practicing during ≥5d/wk. (PR:0.91; 95%CI:0.88-0.94). Compared with <4 h/d of leisure-time sedentary behavior, being socially isolated was also associated with a higher prevalence of 4-7 h/d (PR: 1.08; 95%CI:1.03-1.14) and ≥ 8 h/d (PR: 1.24; 95%CI:1.16-1.33) of leisure-time sedentary behavior. Compared with those participants without elevated leisure-time sedentary behavior and with those practicing adequate physical activity, social isolation was independently associated with a higher prevalence of physical inactivity (PR: 1.20; 95%CI: 1.15-1.26) and elevated leisure-time sedentary behavior (PR: 1.21; 95%CI: 1.14-1.30), as well as with both risk factors simultaneously (PR: 1.36; 95%CI: 1.28-1.45). CONCLUSION: Reducing social isolation could be an important component of future interventions to reduce sedentary behavior and physical inactivity among adolescents.

Are more physical education classes related to less time in leisure-time sedentary behavior? An analysis including adolescents from 73 countries.

This study aimed to verify the association between the weekly frequency of physical education (PE) classes and leisure sitting time among adolescents. We analyzed data from 73 countries using the Global School-based Student Health Survey (283,233 adolescents between 11 and 18 years of age). Leisure sitting time and weekly frequency of PE classes were self-reported. Sex, age, and food insecurity were used as covariates and the analyses were stratified by world regions and country income level. Poisson regression models (random-effects meta-analysis) were used for the main analyses. In comparison with 1 PE class per week (reference group), those with no PE classes presented a lower prevalence of ≥ 3 h/d of leisure sitting time (PR [95%CI] = 0.94 [0.91; 0.98]). On the other hand, adolescents with 2 days (PR [95%CI] = 1.06 [1.02; 1.26]), 3-4 days (PR [95%CI] = 1.17 [1.12; 1.22]), and 5 days (PR [95%CI] = 1.08 [1.04; 1.11]) of PE classes presented a higher likelihood of ≥ 3 h/d of leisure sitting time. No clear differences were observed for the different world regions and country income levels. We conclude that a higher weekly frequency of PE classes is associated with increased leisure sitting time among adolescents worldwide.

The mediation role of social network size and perception in the association between physical activity and depressive symptoms: a prospective analysis from the SHARE study.

OBJECTIVES: To investigate the mediating role of social network size and perceived quality in the associations of physical activity with quality of life and depressive symptoms in middle-aged and older adults. METHOD: We analyzed information of 10,569 middle-aged and older adults from waves 2 (2006-2007), 4 (2011-2012), and 6 (2015) of the Survey of Health, Ageing, and Retirement in Europe study (SHARE). Data on physical activity (moderate and vigorous intensities), social network (size and quality), depressive symptoms (EURO-D scale), and quality of life (CASP) were self-reported. Sex, age, country of residency, schooling, occupational status, mobility, and baseline values of the outcome were used as covariates. We created mediation models to test the mediating effect of social network size and quality in the association between physical activity and depressive symptoms. RESULTS: Social network size partly mediated the association between vigorous physical activity and depressive symptoms (7.1%; 95%CI: 1.7-12.6) as well as the association between moderate (9.9%; 1.6-19.7) and vigorous (8.1%; 0.7-15.4) physical activity and quality of life. Social network quality did not mediate any of the associations tested. CONCLUSION: We conclude that social network's size, but not satisfaction, mediates part of the association of physical activity with depressive symptoms and quality of life in middle-aged and older adults. Future physical activity interventions among middle-aged and older adults should consider increasing social interactions to facilitate benefits for mental health-related outcomes.

Prospective Associations of Leisure-Time Physical Activity With Psychological Distress and Well-Being: A 12-Year Cohort Study.

OBJECTIVE: This study aimed to investigate the associations of leisure-time physical activity with psychological distress and well-being, and potential mediators. METHODS: We used data from the 1970 British Cohort Study (n = 5197; 2688 men), including waves 34y (2004), 42y (2012), and 46y (2016). Participants reported leisure-time physical activity frequency and intensity (exposure) at age 34 years (baseline); cognition (vocabulary test), body mass index, disability, mobility and pain perception (potential mediators) at age 42 years; and psychological distress (Malaise Inventory) and well-being (Warwick-Edinburgh scale) at age 46 years. Baseline confounders included sex, country, education, employment status, alcohol use, tobacco smoking, and psychological distress. Main analyses included logistic regression and mediation models. RESULTS: Higher leisure-time physical activity intensity at baseline was associated with lower psychological distress at 46y (ß = -0.038 [95% confidence interval {CI} =-0.069 to -0.007]), but not leisure-time physical activity frequency. Baseline leisure-time physical activity frequency and intensity were associated with higher psychological well-being at 46y (frequency: ß = 0.089 [95% CI = 0.002 to 0.176]; intensity: ß = 0.262 [95% CI = 0.123 to 0.401]); and total: ß = 0.041 [95% CI = 0.013 to 0.069]). Only body mass index at 42y partially mediated the association between leisure-time physical activity frequency (15.7%) and total leisure-time physical activity (6.2%) at 34y, with psychological well-being at 46y. CONCLUSIONS: Our findings highlight the role of leisure-time physical activity in psychological distress and well-being, with greater effect sizes associated with higher frequency and intensity of leisure-time physical activity. Future interventions should consider examining potential mediators of the association of leisure-time physical activity with psychological well-being, such as body mass index.

Prevalence and sociodemographic correlates of physical activity and sitting time among South American adolescents: a harmonized analysis of nationally representative cross-sectional surveys.

BACKGROUND: To identify the prevalence and sociodemographic correlates of different domains of physical activity (PA) and higher sitting time among South American adolescents. METHODS: Data from national surveys of 11 South American countries were analyzed, and comprised information on 166,901 adolescents. PA (≥ 60 min/day of moderate-vigorous PA), physical education classes (PEC) (≥ 3 classes/wk), active commuting to school (≥ 1 d/wk), and higher sitting time (≥ 3 h/d) were self-reported. Sociodemographic correlates, such as gender, age, and food security status were explored using a random effect meta-analysis for logistic parameters. RESULTS: Recommended PA ranged between 7.5% (Brazil) and 19.0% (Suriname). Peru (2.2%) and Guyana (43.1%) presented the lowest prevalence of PEC and active commuting to school, respectively. Higher sitting time was less prevalent in Bolivia (24.6%) and more prevalent in Argentina (55.6%). Compared to girls, boys were more prone to reach recommendations for PA [OR = 1.94(1.65;2.28)]; to reach ≥ 3 PEC [OR = 1.17(1.04;1.33)] and to be active in commuting to school [(OR = 1.14(1.06;1.23)], but less prone to higher sitting time [OR = 0.89(0.82;0.96)]. Older adolescents had less odds of reach PA guidelines [OR = 0.86(0.77; 0.97)] and accumulated higher sitting time [OR = 1.27(1.14;1.41)]. Adolescents with food insecurity reported more PEC [OR = 1.12(1.04;1.21)] and active commuting to school [OR = 1.12(1.02;1.22)] but had less higher sitting time than their food security pairs [OR = 0.89(0.81;0.98)]. CONCLUSIONS: Few adolescents reach the PA recommendation. Actions aiming the promotion of PA and the reduction of sitting time must consider girls and older adolescents as target groups, as well as the specifics of each country.

Sociodemographic inequalities in the trends of different types of leisure-time physical activity among Brazilian adults between 2006 and 2019.

BACKGROUND: The current study aimed to describe the trends in gender, ethnicity, and education inequalities of types of leisure-time physical activity (LTPA) practiced by Brazilian adults from 2006 to 2019. METHODS: We used data from 2006 to 2019 of the Brazilian Surveillance System for Risk and Protective Factors for Chronic Diseases by Telephone Survey, which is an annual survey with a representative sample of adults (≥ 18y) living in state capital cities. The types of LTPA considered were walking, running, strength/gymnastics, sports, other LTPA, and no LTPA participation. Gender (women or men), ethnicity (white, black, brown, or yellow/indigenous), and years of formal education were also self-reported. We used relative frequencies and their respective 95% confidence intervals to analyze trends. The absolute and relative differences between the proportions were used to assess the inequalities. RESULTS: We observed increases in inequalities related to gender and education (running and strength/gymnastics), while gender inequalities for sports, other types, and no LTPA participation decreased. There were persistent inequalities related to gender (walking) and education (sports, other types, and no LTPA participation). Considering ethnicity, we noted increases in inequality for strength/gymnastics, where white adults were more active than black and brown adults. In addition, white adults reported more access to LTPA than brown adults over the years analyzed. CONCLUSION: Women, black and brown people, and subjects with less schooling were the most unfavored groups. While some inequalities persisted over the years, others increased, such as ethnicity and education inequalities for strength/gymnastics.

Clusters of obesogenic behaviors and metabolic risk according to somatic maturity status among adolescents.

OBJECTIVE: This study aimed to identify the clusters of obesogenic behaviors, and verify the association with metabolic risk according to the categories of somatic maturity status of adolescents. METHODS: This is a cross-sectional study conducted with 1159 (55.1% girls) Brazilian adolescents aged between 10 and 16 years (mean age: 12.9 years). Measurements of waist circumference, blood pressure, blood glucose, HDL-C, and triglycerides were combined to calculate a metabolic risk score. Somatic maturity was assessed by estimating the peak of height velocity. The obesogenic behaviors analyzed were physical activity (Baecke questionnaire), sedentary behavior (screen-based behaviors) and dietary habits (consumption of healthy and unhealthy food). The Two Step clustering algorithm using the log-likelihood measure was employed to cluster formation and regression models were adopted to the main analysis. RESULTS: We observed a complex co-existence of obesogenic behaviors. Differences regarding the metabolic risk between clusters was only observed among the early-maturing adolescents, where the cluster with higher number of healthy behaviors but lower physical activity presented higher metabolic risk score. CONCLUSIONS: We conclude that physical activity has an important role on the association of clusters of obesogenic behaviors and metabolic risk in early-maturing adolescents.

Association of public physical activity facilities and participation in community programs with leisure-time physical activity: does the association differ according to educational level and income?

BACKGROUND: Our aim was to analyze the association of the presence of public physical activity (PA) facilities and participation in public PA programs with leisure-time PA, with an emphasis on the moderating role of educational level and income. METHODS: We used data of 88,531 adults (46,869 women), with a mean age of 47.2 ± 17.1y, from the 2019 Brazilian National Health Survey. Leisure-time PA (dichotomized considering 150 min/week), the presence of a public PA facility near the household (yes or no), participation in public PA programs (yes or no), educational level (divided into quintiles) and per capita income (divided into quintiles) were all self-reported through interviews. Adjusted logistic regression models were used for the analyses. RESULTS: The presence of public PA facilities near the household and the participation in public PA programs were associated with higher leisure-time PA among all quintiles of income and educational level. However, multiplicative interactions revealed that participating in PA programs [Quintile (Q)1: OR: 13.99; 95%CI: 6.89-28.38 vs. Q5: OR: 3.48; 95%CI: 2.41-5.01] and the presence of public PA facilities near the household (Q1: OR: 3.07; 95%CI: 2.35-4.01 vs. Q5: OR: 1.38; 95%CI: 1.22-1.55) were more associated with higher odds of being active in the leisure-time among the lowest quintile of educational level. CONCLUSIONS: The presence of public PA facilities and participation in public PA programs are environmental correlates that may be relevant for designing effective public health interventions to reduce social inequalities in leisure-time PA among adults in low-income areas.

The association between physical activity and mental health during the first year of the COVID-19 pandemic: a systematic review.

INTRODUCTION: The Coronavirus disease-19 (COVID-19) pandemic affected countries worldwide and has changed peoples' lives. A reduction in physical activity and increased mental health problems were observed, mainly in the first year of the COVID-19 pandemic. Thus, this systematic review aims to examine the association between physical activity and mental health during the first year of the COVID-19 pandemic. METHODS: In July 2021, a search was applied to PubMed, Scopus, and Web of Science. Eligibility criteria included cross-sectional, prospective, and longitudinal study designs and studies published in English; outcomes included physical activity and mental health (e.g., depressive symptoms, anxiety, positive and negative effects, well-being). RESULTS: Thirty-one studies were included in this review. Overall, the studies suggested that higher physical activity is associated with higher well-being, quality of life as well as lower depressive symptoms, anxiety, and stress, independently of age. There was no consensus for the optimal physical activity level for mitigating negative mental symptoms, neither for the frequency nor for the type of physical activity. Women were more vulnerable to mental health changes and men were more susceptive to physical activity changes. CONCLUSION: Physical activity has been a good and effective choice to mitigate the negative effects of the COVID-19 pandemic on mental health during the first year of the COVID-19 pandemic. Public health policies should alert for possibilities to increase physical activity during the stay-at-home order in many countries worldwide.

Multimorbidity is associated with TV-viewing, but not with other types of screen-based behaviors in Brazilian adults.

BACKGROUND: The presence of multimorbidity increases the risk of mortality, and identifying correlates of multimorbidity can direct interventions by targeting specific modifiable correlates. Here we aimed to investigate the association between two types of screen-based behaviors and multimorbidity. METHODS: We used data from 87,678 Brazilian adults from the National Health Survey (2019). Multimorbidity (presence of two or more chronic conditions among 12 possibilities), TV-viewing, and time on other types of screens (computer, tablet, or cell phone), were self-reported. Crude and adjusted binary and multinominal logistic regression models were performed stratified by sex, age group, and the number of chronic conditions. RESULTS: Considering adjusted values, 2 h/day as a reference, and reporting values in odds ratio (OR) and prevalence ratio (PR) with 95% confidence intervals (95%CI), multimorbidity presented associations with TV-viewing in general [from OR (95%CI) 1.10 (1.03-1.18) in 2 to < 3 h/d, to OR (95%CI) 1.57 (1.40-1.76) in ≥ 6 h/d], except in 2 to < 3 h/d time category for male and 35 to 49 years, and all time categories for 18 to 34 years. In addition, TV-viewing was associated with an increasing number of chronic conditions, all greater in ≥ 6 h/d [2 conditions - PR (95%CI) 1.24 (1.08-1.43); 3 conditions - PR (95%CI) 1.74 (1.45-2.08); 4 or more conditions - PR (95%CI) 2.29 (1.93-2.73)], except in 2 conditions on 2 to < 3 h/d. Other types of screen-based behaviors were only associated with multimorbidity among males [≥ 6 h/d: OR (95%CI) 1.22 (1.01-1.48)] and older individuals (65 years) in some time categories [3 to < 6 h/d: OR (95%CI) 1.98 (1.42-2.77) and ≥ 6 h/d: OR (95%CI) 1.73 (1.06-2.84)]. CONCLUSION: Intervention strategies for reducing screen time in Brazilian adults should focus mainly on TV-viewing, which seems to be associated with more harmful conditions than time on other types of screen-based behaviors.

Resistance training reduces depressive and anxiety symptoms in older women: a pilot study.

OBJECTIVES: The purposes of this study were to analyze the effect of resistance training (RT) on depressive and anxiety symptomsand examine the possible consequences of age, cognitive alterations, and muscular strength on such symptoms.Method: Forty-one older women (68 ± 8 years) composed a training group (TG) or a control group (CG). The TG was submitted to a supervised, progressive RT program over 12 weeks, involving eight whole-body exercises performed with three sets of 8-12 repetitions, three days per week, whereas CG remains with no intervention for the same period. Muscular strength (one-repetition maximum tests), cognitive function (Montreal Cognitive Assessment - MoCA; Verbal Fluency Tests), depression (15-item eriatric Depression Scale - GDS-15), and anxiety (Beck Anxiety Inventory - BAI) were assessed before and after the intervention period. RESULTS: There were observed significant (P < 0.001) RT-induced improvements on total muscular strength (TG: pre = 122.4 ± 24.1/post = 134.3 ± 36.7; CG: pre = 105.4 ± 15.4/post = 99.2 ± 17.1) and MoCA (TG: pre =21.7 ± 4.5/post = 22.5 ± 4.7; CG: pre = 20.3 ± 3.7/post = 19.3 ± 4.1). Depressive and anxiety symptoms (even when adjusted by chronological age and changes in muscular strength or cognitive function) were reduced with RT according to GDS-15 (TG: pre = 2.26 ± 1.53/post = 1.92 ± 1.68; CG: pre =2.68 ± 1.13/post = 2.25 ± 1.18) and BAI (TG: pre = 4.07 ± 5.68/post = 2.33 ± 3.71; CG: pre = 5.18 ± 7.70/post = 9.81 ± 7.10). The time x group interactions were significant for depressive and anxiety symptoms. CONCLUSIONS: Our results suggest that a 12-week RT program reduces depressive and anxiety symptoms, regardless of age, muscular strength, and cognition function in older women.

Measurement of physical activity and sedentary behavior in national health surveys, South America.

Objectives: To characterize how physical activity and sedentary behavior have been measured in national health surveys in South American countries. Methods: An extensive search was made for national health surveys from all 12 South American countries through health websites, national statistical offices, and contact with researchers and policy-makers. The following eligibility criteria were used to select surveys: conducted in a South American country; used a nationally representative sample ≥ 18 years; coordinated by the public, private or mixed private-public sector; and assessed physical activity and/or sedentary behavior. Data were extracted on general information about the surveys, specific details about the physical activity and sedentary behavior assessment, and additional questions related to activity behavior. Results: In total, 36 surveys were included, two of which were multicountry surveys; all surveys assessed physical activity and 27 assessed sedentary behavior. Most surveys (23/36; 64%) were based on previously validated international questionnaires, but 13 (57%) of these deviated from the reference tools, introducing changes and adaptations. Sedentary behavior was assessed mostly through questions on screen time and/or daily sitting time in the same physical activity questionnaires. No survey used device-based measures to generate data on these behaviors. Conclusions: Differences between instruments used and modifications limit the comparability of data across countries. This highlights the importance of standardizing assessment within South America for physical activity and sedentary behavior sections in national surveys, with the broader aim of contributing to establishing a standardized strategy for the surveillance of physical activity and sedentary behavior in South America.

Device-measured physical activity and sedentary behaviour in relation to mental wellbeing: An analysis of the 1970 British cohort study.

Although physical activity and sedentary behaviour have established associations with mental illness, the extent to which they impact on mental wellbeing is not well understood. We examined associations between moderate to vigorous physical activity (MVPA), sitting time (ST) and mental wellbeing in 4526 participants from the 1970 British Cohort Study (UK) in the age 46 survey (2016-18). MVPA and ST were measured using a thigh mounted accelerometer device (activPAL 3 micro) worn continuously for 7 days and participants completed the 14-item Warwick-Edinburg Mental Wellbeing Scale (WEMWBS) to assess mental wellbeing. In linear regression models MVPA (per hr) was associated with an additional 0.57 points on the WEMWBS (95% CI 0.03-1.12) regardless of gender, wear time, education, socioeconomic status, smoking, body mass index, disability and psychological distress. ST was not associated with WEMWBS in the adjusted models (B = -0.11, -0.23, 0.02). In MVPA stratified analyses, ST showed a linear trend with WEMBS in participants with low levels of MVPA but not in medium and high MVPA categories. In this large, nationally representative cohort, device-measured MVPA showed an association with higher mental wellbeing whilst ST was only associated with reduced mental wellbeing in participants with low levels of MVPA. Our main limitation was the cross-sectional design which precludes any inference of direction of association or causality. Nevertheless, interventions to promote MVPA may be an effective public health policy to promote mental wellbeing. Further investigation of the effect different sitting behaviours has on mental wellbeing is warranted.

Associations between mentally-passive and mentally-active sedentary behaviours during adolescence and psychological distress during adulthood.

It is unclear if different types of sedentary behaviour during the adolescence are differentially associated with psychological distress during adolescence and adulthood. It is also unknown what may mediate this potential proposed association. The current study aimed to analyse the association of mentally-active and mentally-passive sedentary behaviours during adolescence (16y) with subsequent psychological distress during adulthood (42y), and to examine the role of potential mediators (42y). Data from the 1970 British Cohort Study was used (N = 1787). At age 16y participants reported time and frequency in mentally-passive (TV-viewing and watching movies) and mentally-active (reading books, doing homework and playing computer games) sedentary behaviours, psychological distress and organized sports participation. At 42y, participants reported cognition (vocabulary test), TV-viewing, psychological distress, self-rated health, body mass index and employment status. Education was collected throughout the follow-up years. Logistic regression and mediation models assessed associations. Multiple imputation using chained equations was used to assess the impact of missing data. Mentally-passive sedentary behaviour in adolescence was a risk factor for psychological distress during adulthood in complete-cases analysis [OR:1.44(95%CI:1.09-1.90)], which was confirmed by the model with multiple imputation. Mentally-active sedentary behaviour at 16y was not associated with psychological distress at 42y. Adult TV-viewing during weekends (24.7%), and self-rated health (19.0%) mediated the association between mentally-passive sedentary behaviour during adolescence and psychological distress during adulthood. However, the mediation was not clear in the models with multiple imputation. Mentally-passive sedentary behaviour during adolescence was associated with elevated psychological distress during adulthood and this association was mediated TV-viewing and self-rated health in adulthood.

Association of change in the school travel mode with changes in different physical activity intensities and sedentary time: A International Children's Accelerometry Database Study.

Our aim was to assess the association between changes in active travel to school and changes in different intensities of physical activity (i.e. moderate - MPA and vigorous - VPA) and time spent sedentary (SED) among adolescents and assess the moderating effect of children's sex, age and weight status. Data from six cohort studies in the International Children's Accelerometry Database were used (4108 adolescents aged 10-13y at baseline, with 1.9±0.7y of follow-up). Participants self-reported travel mode to school at baseline and follow-up. Mutually exclusive categories of change were created using passive (e.g. by car) or active (cycling or walking) forms of transport (active/active, passive/active, active/passive, passive/passive). Multilevel linear regression analyses assessed associations with change in accelerometer-assessed time spent MPA, VPA and SED, adjusting for potential confounders. The moderation of sex, age and weight status was tested though the inclusion of interaction terms in the regression models. Relative to those remaining in active travel (active/active), participants classified as passive/active increased VPA (B: 2.23 min/d; 95%CI: 0.97-3.48), while active/passive (MPA: -5.38min/d; -6.77 to -3.98; VPA: -2.92min/d; -4.06 to -1.78) and passive/passive (MPA: -4.53min/d; -5.55 to -3.50; VPA: -2.84min/d; -3.68 to -2.01) decreased MPA and VPA. There were no associations with SED. An interaction was observed, age group moderated the association with change in VPA: among 12-13y-olds a greater increase in VPA was observed for the passive/active group compared to active/active. Promoting active travel to school can be a strategy to attenuate the decline in physical activity through adolescence.

Sociodemographic inequities and active transportation in adults from Latin America: an eight-country observational study.

BACKGROUND: Active transportation is a crucial sort of physical activity for developing sustainable environments and provides essential health benefits. This is particularly important in Latin American countries because they present the highest burden of non-communicable diseases relative to other worldwide regions. This study aimed to examine the patterns of active transportation and its association with sociodemographic inequities in Latin American countries. METHODS: This cross-sectional study was conducted in eight countries. Participants (n = 8547, 18-65 years) self-reported their active transportation (walking, cycling, and total) using the International Physical Activity Questionnaire. Sex, age, ethnicity, socioeconomic level, education level, public and private transport use, and transport mode were used as sociodemographic inequities. RESULTS: Participants spent a total of 19.9, 3.1, and 23.3 min/day with walking, cycling, and total active transportation, respectively. Mixed and other ethnicity (Asian, Indigenous, Gypsy, and other), high socioeconomic level as well as middle and high education level presented higher walking than Caucasian, low socioeconomic and education level. Private transport mode and use of ≥ 6 days/week of private transport showed lower walking than public transport mode and ≤ 2 days/week of private transport. Use of ≥ 3 days/week of public transport use presented higher walking than ≤ 2 days/week of public transport. Men had higher cycling for active transportation than women. Use of ≥ 3 days/week of public transport use presented higher cycling than ≤ 2 days/week of public transport. ≥6 days/week showed lower cycling than ≤ 2 days/week of private transport use. Men (b: 5.57: 95 %CI: 3.89;7.26), black (3.77: 0.23;7.31), mixed (3.20: 1.39;5.00) and other ethnicity (7.30: 2.55;12.04), had higher total active transportation than women and Caucasian. Private transport mode (-7.03: -11.65;-2.41) and ≥ 6 days/week of private transport use (-4.80: -6.91;-0.31) showed lower total active transportation than public transport mode and ≤ 2 days/week of private transport use. Use of 3-5 (5.10: 1.35;8.85) and ≥ 6 days/week (8.90: 3.07;14.73) of public transport use presented higher total active transportation than ≤ 2 days/week of public transport use. Differences among countries were observed. CONCLUSIONS: Sociodemographic inequities are associated differently with active transportation across Latin American countries. Interventions and policies that target the promotion of active policies transportation essential to consider sociodemographic inequities. TRIAL REGISTRATION: ClinicalTrials.Gov NCT02226627. Retrospectively registered on August 27, 2014.

Body mass index trajectories and noncommunicable diseases in women: The role of leisure time physical activity.

OBJECTIVE: To analyze the association between body mass index trajectories and non-communicable diseases (NCDs) in women, and the interaction effects of leisure time physical activity on this relationship. METHODS: Sample was composed by 15 628 women (≥30 years old) who performed objective measurement of body mass, height, and blood pressure in the 2013 Brazilian Health Survey (2013). Information regarding the body mass at 20 years old, current type 2 diabetes (T2DM), dyslipidemia diagnosis, and leisure time physical activity were self-reported by the participants. Socio-demographic and behavioral covariates were considered. Logistic regression models were used for the statistical analysis. RESULTS: Those who were obese in both moments and women who become obese showed similar high risk, however, the prevalence of NCDs among women who were no longer obese was similar to the consistently non-obese. Leisure time physical activity attenuated the general deleterious effect of obesity, especially among the consistently obese women for dyslipidemia (inactive: OR: 2.02 [95%CI: 1.69-2.43] vs active: OR: 1.05 [95%CI: 0.55-1.99]), T2DM (inactive: OR: 3.84 [95%CI: 2.72-5.43] vs active: OR: 4.38 [95%CI: 1.49-12.86]) and high blood pressure (inactive: OR: 2.00 [95%CI: 1.56-2.57] vs active: OR: 1.15 [95%CI: 0.57-2.52]). CONCLUSIONS: Changes in body mass index appear to be sensitive to detecting the risk of NCDs over lifespan. In addition, leisure time physical activity attenuates the negative effects of obesity on NCDs, but this appears more important for the consistently non-obese women.

Do TV viewing and frequency of ultra-processed food consumption share mediators in relation to adolescent anxiety-induced sleep disturbance?

OBJECTIVE: To investigate the role of potential shared mediators in the association of TV viewing and frequency of ultra-processed food consumption with anxiety-induced sleep disturbance. DESIGN: Cross-sectional study. SETTING: Data from the Adolescent School-Based Health Survey, a Brazilian nationally representative survey of ninth-grade adolescents conducted in 2015, were used. PARTICIPANTS: 99 791 adolescents (52 015 girls) with a mean age of 14·3 years (range 11-19) participated. All variables were collected through a self-reported questionnaire based on the Global School-Based Student Health Survey. Anxiety-induced sleep disturbance was the outcome. Over 4 h/d of TV viewing and daily consumption of ultra-processed foods were the exposures. Body satisfaction, loneliness, self-rated health and eating while watching TV or studying were mediators. Age, ethnicity, food insecurity, type of city (capital or interior), country region and physical activity were covariates. Logistic regression and mediation models (Karlsson-Holm-Breen method) assessed associations. RESULTS: Both daily ultra-processed food consumption (boys: OR 1·48, 95 % CI 1·30, 1·70; girls: OR 1·46, 95 % CI 1·34, 1·60) and TV viewing (boys: OR 1 24, 95 % CI 1·08, 1·43; girls: OR 1·09, 95 % CI 1·00, 1·19) were associated with higher odds for anxiety-induced sleep disturbance. Loneliness and eating while watching TV or studying (only among girls) consistently mediated the association of both daily ultra-processed food consumption (loneliness: boys 17·4 %, girls 23·4 %; eat while watching TV or studying: girls 6·8 %) and TV viewing (loneliness: boys 22·9 %, girls 45·8 %; eat while watching TV or studying: boys 6·7 %, girls 17·9 %) with anxiety-induced sleep disturbance. CONCLUSIONS: Daily ultra-processed food consumption and TV viewing share mediators and can act in synergic mechanisms in the association with anxiety-induced sleep disturbance. Therefore, future interventions should focus in the reduction of both behaviours in combination.