An examination of school- and student-level characteristics associated with the likelihood of students' meeting the Canadian physical activity guidelines in the COMPASS study

School-level intra-cluster correlation coefficients and autocorrelations for children's accelerometer-measured physical activity in England by age and gender

BACKGROUND

Randomised, cluster-based study designs in schools are commonly used to evaluate children's physical activity interventions. Sample size estimation relies on accurate estimation of the intra-cluster correlation coefficient (ICC), but published estimates, especially using accelerometry-measured physical activity, are few and vary depending on physical activity outcome and participant age. Less commonly-used cluster-based designs, such as stepped wedge designs, also need to account for correlations over time, e.g. cluster autocorrelation (CAC) and individual autocorrelation (IAC), but no estimates are currently available. This paper estimates the school-level ICC, CAC and IAC for England children's accelerometer-measured physical activity outcomes by age group and gender, to inform the design of future school-based cluster trials.

METHODS

Data were pooled from seven large English datasets of accelerometer-measured physical activity data between 2002-18 (> 13,500 pupils, 540 primary and secondary schools). Linear mixed effect models estimated ICCs for weekday and whole week for minutes spent in moderate-to-vigorous physical activity (MVPA) and being sedentary for different age groups, stratified by gender. The CAC (1,252 schools) and IAC (34,923 pupils) were estimated by length of follow-up from pooled longitudinal data.

RESULTS

School-level ICCs for weekday MVPA were higher in primary schools (from 0.07 (95% CI: 0.05, 0.10) to 0.08 (95% CI: 0.06, 0.11)) compared to secondary (from 0.04 (95% CI: 0.03, 0.07) to (95% CI: 0.04, 0.10)). Girls' ICCs were similar for primary and secondary schools, but boys' were lower in secondary. For all ages, combined the CAC was 0.60 (95% CI: 0.44-0.72), and the IAC was 0.46 (95% CI: 0.42-0.49), irrespective of follow-up time. Estimates were higher for MVPA vs sedentary time, and for weekdays vs the whole week.

CONCLUSIONS

Adequately powered studies are important to evidence effective physical activity strategies. Our estimates of the ICC, CAC and IAC may be used to plan future school-based physical activity evaluations and were fairly consistent across a range of ages and settings, suggesting that results may be applied to other high income countries with similar school physical activity provision. It is important to use estimates appropriate to the study design, and that match the intended study population as closely as possible.

Perceived Barriers to Physical Activity Among Youth Living in Rural and Urban Canadian Communities: A Nationally Representative Cross-Sectional Study

BACKGROUND

We used nationally representative data to explore associations among location of residence (rural/urban) and perceived barriers to physical activity (PA) in Canadian youth.

METHODS

We analyzed the 2017 Canadian Community Health Survey, Barriers to Physical Activity Rapid Response data for 12- to 17-year-old youth. Nine items from the survey assessing perceived barriers to PA were combined into 3 barrier domains: resources, motivational, and socioenvironmental. The likelihood of reporting barriers to PA based on rural-urban location was examined using survey-weighted binary logistic regression following a model fitting approach. Sociodemographic factors were modeled as covariates and tested in interaction with location. For each barrier domain, we derived the best-fitting model with fewest terms.

RESULTS

There were no location-specific effects related to reporting any barrier or motivation-related PA barriers. We found a sex by location interaction predicting the likelihood of reporting resource-related barriers. Rural boys were less likely to report resource-related barriers compared with urban boys (odds ratio [OR] = 0.42 [0.20, 0.88]). Rural girls were more likely to report resource-related barriers compared with boys (OR = 3.72 [1.66, 8.30]). Regarding socioenvironmental barriers, we observed a significant body mass index by location interaction demonstrating that rural youth with body mass index outside the "normal range" showed a higher likelihood of reporting socioenvironmental barriers compared with urban youth (OR = 2.38 [1.32, 4.30]). For urban youth, body mass index was unrelated to reporting socioenvironmental barriers (OR = 1.07 [0.67, 1.71]).

CONCLUSION

PA barriers are not universal among Canadian youth. Our analyses highlight the importance of testing interactions in similar studies as well as considering key sociodemographic characteristics when designing interventions.

Comparison of physical activity and physical fitness in children and adolescents of Chinese Han and Tibet ethnicity

Background

Physical activity (PA) and physical fitness (PF) are important markers of health status in children and adolescents in different ethnicities. In this study, we aimed to compare the PA and PF indicators between Tibetan and Han children and adolescents.

Methods

Children and adolescents of 4-9 grades were recruited in Shigatse (n = 963) and Shanghai (n = 2,525) respectively. The information related to demographic, PA, and PF was collected via a self-reported questionnaire. PA was assessed through the participation of moderate to vigorous PA (MVPA), muscle-strengthening exercise (MSE) and organized sport participation (OSP). PF was estimated using the International Fitness Scale containing components of overall fitness, cardiorespiratory fitness, speed and agility, muscular strength and flexibility.

Results

Han (mean age = 13.45 ± 3.3 years; 49.7% girls) and Tibet (mean age = 13.8 ± 2.5 years; 48.3% girls) children and adolescents from Shanghai and Shigatse completed the questionnaire survey. It was revealed that Tibetan students had higher MVPA, MSE and OSP than children and adolescents of Han ethnicity (p < 0.01, small to medium effect size). A relatively higher percentage of student in Shanghai did not participate in any form of PA. On the other hand, less Tibetan students thought their PF indicators including overall fitness, cardiorespiratory fitness, speed and agility, muscular strength and flexibility were poor or very poor than their counterparts of Han ethnicity (p < 0.01, small to medium effect size).

Conclusion

Tibetan children and adolescents have higher levels of PA and PF in comparison to their Han counterparts. More children and adolescents of Han ethnicity engage in no PA and think their PF indicators were poor.

Trajectories of osteogenic physical activity in children and adolescents: A 3-year cohort study

OBJECTIVES

We explored the latent profiles based on locomotor skills and cardiorespiratory fitness in Finnish schoolchildren and examined their associations with latent growth curves of osteogenic physical activity (PA) over three years.

DESIGN

Prospective cohort study.

METHODS

Altogether 1147 Finnish adolescents aged 11-13 years participated in the study. Osteogenic PA in terms of osteogenic index (OI) was calculated based on acceleration peak histograms using all of the peaks with acceleration >1.3 g. Locomotor skills were assessed using the five-leap and side-to-side jumping tests and cardiorespiratory fitness (CRF) using 20-metre shuttle run test. The latent growth curve models for the locomotor skills and cardiorespiratory fitness profiles were tested to examine the longitudinal development of OI scores over time three years (from T0 to T3).

RESULTS

OI scores were lower amongst children in the "Low locomotor profile" compared with "Moderate" and "High locomotor" profiles. The OI scores linearly decreased from T0 to T3 in each locomotor profile and the decrease was similar in all the profiles. Moreover, OI scores were lower in the "Low CRF profile" compared with "Moderate" and "High CRF" profiles. The OI scores decreased in each profile over time, but the decrease was steepest in the "Low CRF profile", whereas "Moderate" and "High CRF profiles" had similar developmental trajectories.

CONCLUSIONS

Children with the highest locomotor skills and higher CRF accumulate more osteogenic PA than their least skilful and fit peers, which can have important implications on bone health in this critical period for bone growth.

Association Between Frequency of Muscle-Strengthening Exercise and Depression Symptoms Among Middle and High School Students: Cross-Sectional Survey Study

BACKGROUND

Existing literature on the association between the frequency of muscle-strengthening exercise (MSE) and depression among adolescents is limited and contradictory.

OBJECTIVE

This study aimed to elucidate the association of MSE frequency with depression symptoms among middle and high school students in China.

METHODS

A total of 27,070 students in grades 7-12 from 376 middle and high schools were surveyed using an anonymous self-administered questionnaire between April and June 2022. Information on engaging in MSE was self-reported, and depression symptoms were assessed using the Patient Health Questionnaire-9 (PHQ-9). Poisson regression was used to examine the association between MSE frequency and depression symptoms.

RESULTS

Among the 27,006 eligible students, 51.6% (n=13,933) were boys, and the mean age was 15.6 (SD 1.7) years. The overall prevalence of meeting MSE recommendations (ie, engaging in MSE ≥3 days/week) was 34.6% (95% CI 32.6%-36.6%; n=9145); the prevalence was higher in boys (43.8%, 95% CI 41.8%-45.8%; 6067/13,933) than in girls (24.3%, 95% CI 22%-26.6%; 3078/13,073; P<.001). A total of 5882 (21.8%) students reported having depression symptoms. After adjustment for sociodemographic status, lifestyle factors, academic performance, and experience of physical fighting, compared to students who did not engage in MSE, the prevalence ratios (PRs) for depression symptoms were 0.98 (95% CI 0.97-0.99) for those engaging in MSE once a week, 0.95 (95% CI 0.93-0.97) for 2 days/week, 0.93 (95% CI 0.90-0.96) for 3 days/week, 0.90 (95% CI 0.87-0.94) for 4 days/week, 0.88 (95% CI 0.84-0.93) for 5 days/week, 0.86 (95% CI 0.81-0.92) for 6 days/week, and 0.84 (95% CI 0.78-0.90) for 7 days/week, respectively.

CONCLUSIONS

The overall prevalence of meeting MSE recommendations among Chinese adolescents is low. The frequency of MSE was inversely associated with depression symptoms.

Unveiling the relationship of physical literacy with muscular fitness and muscle-strengthening activities in adolescents: the EHDLA study

Objective

This study evaluated the relationship between physical literacy (PL) and muscular fitness (MF) as well as muscle-strengthening activities (MSA) in adolescents.

Methods

A secondary cross-sectional study included 823 adolescents (45.1% boys) from the Eating Healthy and Daily Life Activities Study. The Spanish Perceived Physical Literacy Instrument for Adolescents (S-PPLI) assessed the participants' perceived PL. The evaluation of MF in the young population was conducted using the Assessing the Levels of Physical Activity and Fitness (ALPHA-FIT) test battery. MSA were assessed by the following question: 'In the past week, how many days did you exercise to strengthen or tone the muscle, such as through push-ups, sit-ups or lifting weights?' To examine the associations between S-PPLI scores and handgrip strength, standing long jump and MSA days in adolescents, we employed generalised additive models.

Results

Participants with high perceived physical literacty (PPL) had the highest handgrip strength (mean=25.1; PPL had the highest handgrip strength (mean=25.1; bias-corrected and accelerated (BCa) bootstrapped 95% CI 24.2 to 26.0) and standing long jump (mean=149.7; confidence interval (CI) 24.2 to 26.0) and standing long jump (mean=149.7; 24.2 to 26.0) and standing long jump (mean=149.7; BCa bootstrapped 95% CI 145.8 to 153.5). Conversely, those adolescents with low PPL had the lowest handgrip strength (mean=23.1; BCa bootstrapped 95% CI 22.3 to 23.8) and standing long jump (mean=137.3; BCa bootstrapped 95% CI 133.9 to 140.6). For MSA, adolescents with high PPL had the highest mean of MSA days (mean=3.0; BCa bootstrapped 95% CI 2.8 to 3.3), while the lowest mean was observed for those with low PPL (mean=2.0; BCa bootstrapped 95% CI 1.8 to 2.2).

Conclusion

A high level of PL was associated with higher levels of MF and MSA among Spanish adolescents.

Identifying latent classes of physical activity profiles over time among adolescents in Ontario, Canada

BACKGROUND

Physical activity behaviours are known to be highly correlated. Adolescents who participate in one type of physical activity (e.g., physical education) have a greater likelihood of participating in other physical activities (e.g., organized sports); however, little research has examined participation rates in various physical activity behaviours concurrently. This study identified longitudinal physical activity profiles among secondary school aged youth in Ontario, Canada.

METHODS

We used data from the COMPASS Study, a school-based prospective cohort study of adolescents in Canada. Using a repeated measures latent class analysis, Ontario students who participated in grade 9 PE in 2015-16 were analysed through to 2018-19 (n = 1,917). Latent classes were defined by: PE participation, guideline adherence (≥ 60 min/day of moderate to vigorous activity over the last 7 days), and sport participation (varsity, community, and/or intramural). Multinomial logistic regression models were used to examine associations between latent class membership and student characteristics.

RESULTS

Three distinct latent classes were identified for females and four were identified for males. These classes were: (1) Guidelines (high probability of guideline adherence; females: 44%; males: 16%), (2) PE & Sports (high probability of PE and sport participation; females: 33%; males: 43%), (3) Guidelines & Sports (high probability of guideline adherence and sport participation; females: 23%; males: 23%;), and (4) Inactive (low probability of all physical activity indicators; males: 18%). Strength training, sleep, and English grade were associated with class membership among females. Ethno-racial identity, weekly spending money, strength training, and English and math grades were associated with class membership among males.

CONCLUSIONS

Findings suggest that latent physical activity profiles differ by sex. Guideline adherence was the most common class among females, indicating high levels of independent physical activity, whereas PE & Sport participation was the most common class among males, indicating greater tendency towards organized activities. Additionally, a substantial number of male students were not engaging in any physical activity. Participation in both PE and sports did not necessarily lead to meeting physical activity guidelines, highlighting that these activities alone may not be providing sufficient levels of physical activity that align with current recommendations for Canadian youth.

Can Moving More and Sitting Less Improve the Academic Engagement of Adolescents?- A Study Based on Junior High School Students in Shanghai, China

Purpose

The purpose of this study was to examine the relationships between academic engagement and moderate-to-vigorous physical activity (MVPA), muscle-strengthening exercise (MSE) and sedentary behavior (SB) among adolescents, so as to provide evidence from the perspective of exercising for students to learn efficiently, teachers to improve classroom teaching, and schools to improve educational quality.

Methods

A questionnaire survey was conducted in 12 junior high schools in Shanghai, China, which were selected by a multi-stage stratified cluster sampling method. Then, with the valid data of 2078 students collected from the survey. A data analysis was performed using SPSS Statistics 26.0. Multiple linear regression models were adopted to analyze the factors affecting adolescent academic engagement and to determine whether MVPA, MSE, and SB play roles in it.

Results

(1) The differences in academic engagement depended on the exercise adherence to the recommended amount of MVPA, MSE, and screen-based SB. (2) In terms of the three independent variables of total time, MSE (β = 0.206) and MVPA (β = 0.175) showed a significant positive correlation with academic engagement, while SB (β = -0.155) was negatively correlated with academic engagement. (3) From the linear regression model of eight combination groups divided by the exercise adherence to the recommended amount of MVPA, MSE and SB, the group that met none of the recommendations (β = -0.235) showed a significant negative effect on academic engagement, while the groups that met any two or all three of the recommendations demonstrated strong positive correlations with academic engagement (P < 0.001).

Conclusion

Increasing adolescents' muscle-strengthening exercise and moderate-to-vigorous physical activity and reducing sedentary behavior can effectively promote academic engagement. Therefore, adolescents are suggested to reach the recommended amounts of physical activity, muscle-strengthening exercise, and sedentary behavior so as to improve academic engagement more effectively.

Do school characteristics, based on the Comprehensive School Health Framework, contribute to youth meeting national physical activity recommendations over time?

INTRODUCTION

Canadian youth are insufficiently active, and schools may play a role in promoting student physical activity (PA). Based on the Comprehensive School Health (CSH) framework, this study examined whether school characteristics are associated with secondary school students meeting national PA recommendations over time.

METHODS

We used COMPASS survey data from 78 schools in Ontario and Alberta and 9870 Grade 9 and 10 students attending those schools. Students who provided two years of linked PA data (2013/14 and 2015/16) and gender were included. Multilevel analysis was conducted by gender, evaluating the relationship of school-level characteristics (guided by CSH) with students achieving all three PA recommendations after two years (≥ 60 min/day of moderate-to-vigorous PA, vigorous PA ≥ 3 days/week, strengthening activities ≥ 3 days/week).

RESULTS

More than half (56.9%) of students achieving the PA recommendations at baseline were no longer achieving them after two years, and just a quarter (25.6%) of students not achieving the recommendations at baseline achieved them after two years. School-level factors were significantly associated with students achieving the recommendations, but these factors differed by student strata (i.e. by gender and baseline PA status). Generally, student access to equipment, public health partnerships and staff time for health were associated with increased odds of achieving the PA recommendations for certain students.

CONCLUSION

Modifications to school characteristics within CSH may play a role in supporting students in achieving or continuing to achieve the PA recommendations after two years. Further research is needed to better understand the underlying dynamics of the observed relationships.

Correlates of Meeting the Muscle-Strengthening Exercise Guidelines in Children and Adolescent

This study aimed to explore the potential correlates of muscle-strengthening exercise (MSE) in Chinese children and adolescents. A convenient sample (n = 3733) was recruited into this study. Self-reported questionnaires were used to collect information on sex, grade, ethnicity, residence, family composition, moderate to vigorous physical activity (MVPA), family income, parent's education level and MSE in children and adolescents as well as their parent(s). The prevalence of meeting the MSE guidelines was 62.1%. Children and adolescents who were in primary or middle school were more likely to meet the MSE guidelines ([primary school] OR = 2.33, 95% CI: 1.16-4.68; [middle school] OR = 4.62, 95% CI: 2.27-9.39). Children and adolescents with Han ethnicity had a higher likelihood to meet the MSE guidelines (OR = 1.97, 95% CI: 1.37-2.83). Children and adolescents meeting the MVPA recommendation were more likely to meet the MSE guidelines (OR = 5.41, 95% CI: 3.97-7.37). Relative to those who had a parent not meeting the MSE guidelines, those with either father or mother meeting the MSE guidelines were more likely to meet the MSE guidelines (OR = 1.32, 95% CI: 1.13-1.55). Our study may offer evidence for future MSE interventions in Chinese children and adolescents.

Prevalence and correlates of meeting the muscle-strengthening exercise recommendations among Chinese children and adolescents: Results from 2019 Physical Activity and Fitness in China-The Youth Study

PURPOSE

This study aimed to describe the national prevalence of Chinese children and adolescents who met the World Health Organization muscle-strengthening exercise (MSE) recommendations and identify correlates of meeting the MSE recommendations.

METHODS

Cross-sectional data from the 2019 Physical Activity and Fitness in China-The Youth Study, a nationally representative sample of Chinese children and adolescents (n = 80,413; mean age = 13.7 years; 53.9% girls) and their parents, were analyzed. Children and adolescents who reported engaging ≥3 days (up to 7 days) of MSE per week were classified as meeting the MSE recommendations. MSE, demographics, lifestyle behaviors (sport participation, moderate-to-vigorous physical activity, screen time, and sleep duration), exercise intention, peer and parental support, and parental MSE participation were assessed through self-reports. Logistic regression models were used to determine the correlates of meeting the MSE recommendations. The analyses were completed in 2020.

RESULTS

Overall, 39.3% of children and adolescents met the MSE recommendations. Girls, 10th-12th graders, minorities, those from lower income households and those from families with lower parental education were less likely to meet the MSE recommendations. Children and adolescents who were proficient in ≥2 sports were more likely to meet the MSE recommendations (adjusted odds ratio (aOR) = 1.44, 95% confidence interval (95%CI): 1.26-1.65), as were those with more moderate-to-vigorous physical activity (aOR = 1.57, 95%CI: 1.53-1.61). Additionally, children and adolescents with high exercise intention (aOR = 1.60, 95%CI: 1.51-1.69), those whose parents met the adult MSE recommendations (aOR = 1.46, 95%CI: 1.40-1.52), and those who received high peer (aOR = 1.27, 95%CI: 1.20-1.34) and parental support (aOR = 1.07, 95%CI: 1.04-1.12) were more likely to meet the MSE recommendations.

CONCLUSION

Less than two-fifths of Chinese children and adolescents met the World Health Organization MSE recommendations. The correlates identified in our study can help inform the development of school and community based strategies and policies to enhance participation in MSE and improve muscular fitness of all Chinese children and adolescents.

A Comparison of Meeting Physical Activity and Screen Time Recommendations between Canadian Youth Living in Rural and Urban Communities: A Nationally Representative Cross-Sectional Analysis

Meeting the physical activity (PA) and recreational screen time recommendations for children and young people is associated with several health benefits. The purpose of this study was to compare the odds of meeting PA and recreational screen time recommendations between the Canadian youth living in urban versus rural communities. We analyzed nationally representative cross-sectional data collected as part of the 2017–2018 cycles of the Canadian Community Health Survey among young people aged 12–17 years. PA and screen time were self-reported. Sex-specific multivariable logistic regression models were used to estimate the odds of meeting individual and combined PA and recreational screen time recommendations by rural and urban status after adjusting for individual, socioeconomic, and seasonal covariates. The odds of meeting the PA recommendation were not statistically significantly different among males (OR = 1.01, 95% CI: 0.86–1.18) or females (OR 1.05, 95% CI: 0.99–1.11) living in urban versus rural communities. The odds of meeting the recreational screen time recommendations were statistically significantly lower among male (OR = 0.71, 95% CI: 0.65–0.77) and female (OR = 0.71, 95% CI: 0.59–0.86) youth living in urban compared to those in rural communities. The odds of meeting the combined PA and screen time recommendations were statistically significantly lower among urban males (OR = 0.75, 95% CI: 0.71–0.81) but not females (OR = 0.82, 95% CI: 0.58–1.15) than those from rural communities. These findings suggest that residential context (i.e., urban versus rural) may have a differential impact on meeting the combined PA and screen time recommendations among the male and female Canadian youth. Future research should investigate these differences using device-based measures.

Fair play? Participation equity in organised sport and physical activity among children and adolescents in high income countries: a systematic review and meta-analysis

BACKGROUND

Physical activity and sport have numerous health benefits and participation is thought to be lower in disadvantaged children and adolescents. However, evidence for the disparity in physical activity is inconsistent, has not been reviewed recently, and for sport has never been synthesised. Our aim was to systematically review, and combine via meta-analyses, evidence of the socioeconomic disparities in physical activity and sport participation in children and adolescents in high income countries.

METHODS

We conducted searches of five electronic databases using physical activity, sport, and socioeconomic disparity related terms. Two independent reviewers assessed 21,342 articles for peer-reviewed original research, published in English that assessed socioeconomic disparities in physical activity and sport participation in children and adolescents. We combined evidence from eligible studies using a structural equation modelling approach to multilevel meta-analysis.

RESULTS

From the 104 eligible studies, we meta-analysed 163 effect sizes. Overall, children and adolescents living in higher socioeconomic status households were more likely to participate in sport (OR: 1.87, 95% CIs 1.38, 2.36) and participated for a longer duration (d = 0.24, 95% CIs 0.12, 0.35). The socioeconomic disparity in the duration of sport participation was greater in children (d = 0.28, 95% CIs 0.15, 0.41) compared with adolescents (d = 0.13, 95% CIs - 0.03, 0.30). Overall, children and adolescents living in higher socioeconomic status households were more likely to meet physical activity guidelines (OR: 1.21, 95% CIs 1.09, 1.33) and participated for a longer duration (d = 0.08, 95% CIs 0.02, 0.14). The socioeconomic disparity in the duration of total physical activity between low and high socioeconomic status households was greater in children (d = 0.13, 95% CIs 0.04, 0.21) compared with adolescents (d = 0.05, 95% CIs - 0.05, 0.15). There was no significant disparity in leisure time physical activity (d = 0.13, 95% CIs - 0.06, 0.32).

CONCLUSIONS

There was evidence of socioeconomic disparities in sport participation and total physical activity participation among children and adolescents. Socioeconomic differences were greater in sport compared to total physical activity and greater in children compared with adolescents. These findings highlight the need importance of targeting sport programs according to socio-economic gradients, to reduce inequities in access and opportunity to organised sport.

The Eating Healthy and Daily Life Activities (EHDLA) Study

BACKGROUND

Childhood obesity is one of the greatest public health concerns facing advanced societies, Spain being one of the countries with the highest incidence. In this sense, the Region of Murcia has been pointed out as the Spanish autonomous community with the highest prevalence of excess weight among young people. More specifically, the Valle de Ricote has shown an even greater proportion of excess weight among young people. Several sociodemographic, environmental, lifestyle, health-related, cognitive, and psychological factors are related to excess weight. Based on the lack of information, this research project will try to provide relevant information to design intervention programs, as well as to implement effective public policies to try and reverse this alarming situation. Therefore, this research project aims (1) to obtain cross-sectional and longitudinal data on the excess weight and their potential sociodemographic, environmental, lifestyle, health-related, cognitive, and psychological factors associated among adolescents from the Valle de Ricote (Region of Murcia, Spain) (aged 12-17 years), and (2) to examine the association between excess weight and their potential sociodemographic, environmental, lifestyle, health-related, cognitive, and psychological factors associated among this population.

METHODS

A cross-sectional study and follow-up study will be performed. This research project will involve adolescents using a simple random sampling technique. A total of three secondary schools from the Valle de Ricote (Region of Murcia, Spain) will be included in this project. The minimum sample size will be 1138, establishing a 95% confidence interval, a 40% prevalence of excess weight, a 3% margin of error, and a non-response rate of 10%. Primary outcome measures will be: (1) anthropometric measurements, (2) sociodemographic factors, (3) environmental factors, (4) lifestyle factors, (5) health-related factors, (6) cognitive factors, and (7) psychological factors.

CONCLUSION

This research project will aim to determine the prevalence of excess weight and interrelate their potential sociodemographic, environmental, lifestyle, health-related, cognitive, and psychological factors associated. The obtained results will help to manage and propose possible multidisciplinary interventions and strategies in order to prevent and reduce the excess weight in adolescents from the Valle de Ricote. Furthermore, orientations will be given to transfer the obtained results to the public sector to evaluate or change the adopted policies.

Students' perceptions of school sugar-free, food and exercise environments enhance healthy eating and physical activity

OBJECTIVE

The objective of this study was to examine the relationships between students' perceptions of their school policies and environments (i.e. sugar-sweetened beverages (SSB) free policy, plain water drinking, vegetables and fruit eating campaign, outdoor physical activity initiative, and the SH150 programme (exercise 150 min/week at school)) and their dietary behaviours and physical activity.

DESIGN

Cross-sectional study.

SETTING

Primary, middle and high schools in Taiwan.

PARTICIPANTS

A nationally representative sample of 2433 primary school (5th-6th grade) students, 3212 middle school students and 2829 high school students completed the online survey in 2018.

RESULTS

Multivariate analysis results showed that after controlling for school level, gender and age, the students' perceptions of school sugar-free policies were negatively associated with the consumption of SSB and positively associated with consumption of plain water. Schools' campaigns promoting the eating of vegetables and fruit were positively associated with students' consumption of vegetables. In addition, schools' initiatives promoting outdoor physical activity and the SH150 programme were positively associated with students' engagement in outdoor physical activities and daily moderate-to-vigorous physical activity.

CONCLUSIONS

Students' perceptions of healthy school policies and environments promote healthy eating and an increase in physical activity for students.

The epidemiology of muscle-strengthening activity among adolescents from 28 European countries

AIMS

This study aimed to describe the prevalence and socio-demographic and lifestyle-related correlates of muscle-strengthening activity (MSA; strength/resistance training, sit-ups/push-ups, etc.) among a large sample of European adolescents.

METHODS

Data were drawn from the European Health Interview Survey Wave 2 (2013-2014), including 8818 adolescents (15-17 years) from 28 European countries. Self-reported MSA was assessed using a previously validated survey item. Population-weighted prevalence ratios were calculated for (a) 'none' (0 days/week), (b) 'insufficient MSA' (1-2 days/week) or (c) 'sufficient MSA' (⩾3 days/week). Generalised linear models using Poisson regression with robust error variance were used to calculate the prevalence ratios for adolescents reporting sufficient MSA by socio-demographic/lifestyle characteristics and by European region.

RESULTS

Overall, 19.4% (95% confidence interval (CI) 18.3-20.7) reported sufficient (⩾3 days/week) MSA and 57.9% (95% CI 56.4-59.6) reported none. Females, adolescents from Southern and Eastern European regions, those not meeting the aerobic guideline and adolescents classified as overweight were significantly associated with a lower likelihood of reporting sufficient MSA, independent of other characteristics.

CONCLUSIONS

The majority of European adolescents do not meet the MSA guidelines. Future large-scale MSA public-health interventions should target female and currently inactive adolescents, as well as those from Southern and Eastern European regions.

Implementation at-scale of school-based physical activity interventions: A systematic review utilizing the RE-AIM framework

School-based interventions can increase young people's physical activity levels, but few are implemented at-scale (i.e., the expanded delivery of efficacious interventions under real-world conditions into new/broader populations). The Reach, Effectiveness, Adoption, Implementation, and Maintenance (RE-AIM) framework can be used to describe the extent to which interventions have been implemented at-scale. The aim of our review was to determine the extent to which studies of school-based physical activity interventions implemented at-scale reported information across the RE-AIM dimensions. We conducted a systematic search of seven electronic databases to identify studies published up to June 2019. A total of 26 articles (representing 14 individual studies) met the inclusion criteria and were analyzed. Eleven studies reported actual or estimated number of students exposed to the intervention; however, the representativeness of these students was rarely reported. Nine studies reported the intervention effect on the primary outcome during scale-up. Ten studies reported the rate of participating schools/teachers; however, none reported on the characteristics of adopters/nonadopters. Eight studies reported intervention fidelity. Eleven studies described the extent to which the intervention was sustained in schools. There was considerable variability in the reporting of RE-AIM outcomes across studies. There is a need for greater consistency in the evaluation, and reporting of, school-based physical activity interventions implemented at-scale.

The Direct and Indirect Relationships Within the Extended Trans-contextual Model for Moderate-to-vigorous Physical Activity

Given the low levels of physical activity (PA) in adolescence, there are challenges to increasing students' PA outside of the school setting. Thus, researchers emphasize the supportive role that physical education (PE) teachers can play in PA motivation both in and out of school. The aim of the present study was to examine an expanded trans-contextual model (TCM) model for the transit of teachers' perceived support of students' autonomy in terms of contextual and situational motivation in PE to objectively measured moderate-to-vigorous physical activity (MVPA) in PE across different PE contents as well as to the motivational sequence for, and participation in, subjective MVPA during leisure time. This cross-sectional study involved 283 high school students, of whom 43.9% were boys. The autonomous support students received and other motivational factors and objective measures of MVPA in PE and subjective MVPA in leisure time were measured. The results indicate that support for autonomy was significantly and directly related to needs satisfaction (β = 0.61, p < 0.001) and indirectly to autonomous motivation in PE (β = 0.19, p < 0.001) and leisure time (β = 0.16, p < 0.001), intention in PE (β = 0.03, p < 0.05) and leisure time (β = 0.07, p < 0.001), and leisure time MVPA (β = 0.04, p < 0.001), although not MVPA in PE. Gender was a significant covariate for both MVPA in PE (β = -0.62, p < 0.001) and MVPA in leisure time (β = -0.37, p < 0.001), with higher MVPA in boys than girls. This study filled a gap in the scientific literature by demonstrating the full motivational sequence resulting in actual MVPA in PE classes. It also demonstrated that the main goal of PE of enhancing PA not only in school but also outside of school is working. The main motivator is needs satisfaction based on PE teachers' support.

Sex-Related Differences in Adolescent Cannabis Use: Influences of School Context and School Connectedness

BACKGROUND

Boys use cannabis at a younger age and more frequently than girls. It has been suggested these sex differences might vary according to students' relationship to school. We explored whether the association between sex and adolescents' cannabis use varies among schools and according to students' school connectedness.

METHODS

The study population consisted of all students from 11 secondary schools in the greater Québec City area. The sample included 6185 respondents in years 1 to 5 at the secondary level (equivalent to grades 7-11). Study outcomes were monthly cannabis use and early cannabis use.

RESULTS

The association between sex and monthly cannabis use varied significantly among schools after controlling for students' main characteristics and school socioeconomic environment. We found a statistically significant modifying effect of school connectedness on the association between sex and monthly cannabis use. For early cannabis use, we found no modifying effect of school connectedness nor any association with sex.

CONCLUSIONS

Measures to reduce adolescents' cannabis use could be better adapted to local context and more tailored to specific higher-risk groups. School connectedness is a protective factor for cannabis use, although this effect appears stronger for girls than boys.

A systematic review of physical activity, sedentary behavior, and substance use in adolescents and emerging adults

The transition from adolescence into emerging adulthood is marked by changes in both physical activity and substance use. This systematic review characterized associations between movement behaviors (physical activity, sedentary behavior) and frequently used substances (alcohol, cannabis) among adolescents and emerging adults to inform lifestyle interventions that target multiple behavior change outcomes. This systematic review was guided by PRISMA. Electronic databases of PubMed, PsycINFO, and Web of Science were searched from inception through June 25, 2019. The search was designed to identify empirical studies reporting an association between physical activity or sedentary behavior and alcohol or cannabis, with search criteria determining eligibility based on several sampling characteristics (e.g., participants under 25 years of age). After identifying and screening 5,610 studies, data were extracted from 97 studies. Physical activity was positively associated with alcohol use among emerging adults, but the literature was mixed among adolescents. Sedentary behavior was positively associated with alcohol and cannabis use among adolescents, but evidence was limited among emerging adults. Self-report measures were used in all but one study to assess these behaviors. Physical activity is linked to greater alcohol use among emerging adults. Whereas existing studies demonstrate that sedentary behavior might serve as a risk marker for alcohol and cannabis use among adolescents, additional primary research is needed to explore these associations in emerging adults. Future work should also use device-based measures to account for timing of and contextual features surrounding activity and substance use in these populations.

Exploring gender differences in the longitudinal association between bullying and risk behaviours with Body Mass Index among COMPASS youth in Canada

The purpose of this study was to identify gender differences in the association between bullying and Body Mass Index (BMI) longitudinally. Longitudinal data (2013-2015) from 4510 youth (Ontario, Canada) were used to model BMI with consecutive bullying status prospectively, adjusting for previously identified gender-specific health risk behaviour latent classes. To assess for gender differences, these mixed-effects models were stratified by gender. Youth who were victims of bullying (VoB) were more active, engaged in more substance use and reported higher BMI than their non-victim of bullying (NVoB) peers. The gender-specific mixed-models showed that there are gender differences in the association between bullying and BMI. Among females, repeated bullying was associated with higher odds of having overweight/obesity [by 51% (95% C.I. = 1.03, 2.23)] at follow-up. Among male youth, being a VoB at the previous wave only, was associated with higher odds of having overweight/obesity [by 60% (95% C.I. = 1.11, 2.29)] at follow-up. In contrast with previous literature that measured BMI during adulthood (i.e., years after school victimization), our study adds a unique contribution to the literature that across one year (while youth are still in secondary school), bullying is associated with higher odds of weight status and BMI among female and male youth. Since this increase occurs during secondary school, school-based programs aimed at decreasing youth bullying behaviours and addressing increases in BMI before youth leave school are of paramount importance.

Gender differences in the longitudinal association between multilevel latent classes of chronic disease risk behaviours and body mass index in adolescents

INTRODUCTION

Few studies have assessed the relationship between chronic disease risk behaviours and body mass index (BMI) in a longitudinal, sex/gender-specific context. This study used gender-specific analyses to assess the extent to which chronic disease risk behaviour latent classes are associated with BMI and weight status at follow-up.

METHODS

Longitudinal data from 4510 students in Grades 9 to 12, tracked from 2013- 2015, who participated in the COMPASS study were used to assess gender differences in the lagged association between previously determined latent classes (of physical activity and substance use) with BMI using multilevel mixed-effects models. Our multilevel regression models assessed the association between two latent classes, active experimenters and inactive non-using youth, with BMI when stratified by gender.

RESULTS

Male inactive non-substance-using youth were associated with a 0.29 higher continuous BMI (95% CI: 0.057, 0.53) and odds of overweight/obesity increased by 72% (OR = 1.72, 95% CI: 1.2, 2.4) for binary BMI at follow-up relative to active youth who experiment with substance use. No significant associations were detected in females.

CONCLUSION

Over time, physical activity has a protective role on BMI in male youth. Both substance use and physical inactivity should be addressed in obesity prevention efforts. Gender stratification in analyses is also important since females and males have different contributing factors to increases in BMI.

Factors Associated with Students Meeting Components of Canada's New 24-Hour Movement Guidelines over Time in the COMPASS Study

This study aimed to determine if secondary school students are meeting the new Canadian 24-Hour Movement Guidelines (24-MG), as well as each individual recommendation (physical activity; sleep; sedentary behavior) within the 24-MG, and which student-level characteristics predict meeting the 24-MG, both cross-sectionally and longitudinally. This study is the first to examine longitudinal changes in students meeting the 24-MG, as well as student-level characteristics that were predictive of favourable shifts in movement patterns. Cross-sectional data were obtained for 11,793 grade 9 students across Canada as part of the COMPASS study. Of this sample, 3713 students provided linked follow-up data from grade 9 to grade 12. The probability of meeting the guidelines was modeled using two-level logistic regression analyses, adjusting for student-level co-variates and school clustering. Only 1.28% (p < 0.0001) of the sample met the overall 24-MG. Among grade 9 students, 35.9% (p < 0.0001), 50.8% (p < 0.0001), and 6.4% (p < 0.0001) were meeting the individual recommendations for physical activity, sleep, and screen time, respectively. Of those students, less than half were still meeting them by grade 12. Community sport participation was the only predictor of all three individual recommendations within the 24-MG. Longitudinal analyses found that community sport participation and parental support and encouragement were significantly associated with Grade 12 students starting to meet the physical activity and screen time recommendations, respectively, after having not met them in grade 9. Findings can be used to inform policy and public health practice, as well as to inform future research examining causal relationships between the variables.

Individual- and environmental-related correlates of moderate-to-vigorous physical activity in 11-, 13-, and 15-year-old Finnish children

The objective of this study was to analyze the associations of various individual- and environmental-related factors with subgroups of daily, frequent, moderate and low moderate-to-vigorous physical activity (MVPA) among children and adolescents. Data were obtained from the Finnish School-age Physical Activity (FSPA) study 2016 from 4677 national representative 11-, 13-, and 15-year-old children and adolescents. MVPA and individual- and environmental-related factors were assessed by a questionnaire and analyzed by two-level logistic regression. Seventeen of the twenty-one variables were statistically significantly associated with MVPA. However, only three variables were statistically significant in all MVPA subgroups, whereby self-directed PA at least twice a week, fewer perceived barriers, and higher peer support increased the odds of participating in more MVPA. The results from this study showed essential differences among the MVPA subgroups, also supporting previous findings, whereby various individual- and environmental-based factors are associated with children and adolescents’ levels of MVPA. Challenges to designing and implementing effective interventions are based on the need to account for individual differences within the population, as well as the varied connections between PA with different social and physical environments where children and adolescents’ PA takes place. PA interventions with various actions at multiple levels are warranted.

A Multilevel Analysis of Neighbourhood, School, Friend and Individual-Level Variation in Primary School Children's Physical Activity

Physical activity is influenced by individual, inter-personal and environmental factors. In this paper, we explore the variability in children's moderate-to-vigorous physical activity (MVPA) at different individual, parent, friend, school and neighbourhood levels. Valid accelerometer data were collected for 1077 children aged 9, and 1129 at age 11, and the average minutes of MVPA were derived for weekdays and weekends. We used a multiple-membership, multiple-classification model (MMMC) multilevel model to compare the variation in physical activity outcomes at each of the different levels. There were differences in the proportion of variance attributable to the different levels between genders, for weekdays and weekends, at ages 9 and 11. The largest proportion of variability in MVPA was attributable to individual variation, accounting for half of the total residual variability for boys, and two thirds of the variability for girls. MVPA clustered within friendship groups, with friends influencing peer MVPA. Including covariates at the different levels explained only small amounts (3%-13%) of variability. There is a need to enhance our understanding of individual level influences on children's physical activity.

A gender-stratified, multilevel latent class assessment of chronic disease risk behaviours' association with Body Mass Index among youth in the COMPASS study

This paper sought to examine chronic disease risk behaviour latent classes and their association with Body Mass Index (BMI), assessing for gender differences. Participants were youth (n = 116,086; grades 9-12) enrolled in the COMPASS study (Ontario, Canada) during 2013, 2014, 2015. Multilevel latent class analysis was used to identify underlying, homogenous classes of youths' engagement in physical activity, smoking, binge drinking and marijuana use. Adjusted multilevel models regressed BMI on the latent classes controlling for ethnicity and grade. Three latent classes were identified: active experimenters (ACE), inactive clean youth (INC) and inactive substance users (INSU). This study found that gender differences are apparent in chronic disease risk behaviour latent classes and their association with BMI. INC males (OR = 0.85, 95% CI = 0.78, 0.93) were associated with a lower odds of overweight/obesity relative to active males who experimented with substance use. As for females, the class with the highest proportion of youth using substances were associated with higher odds (Females: OR = 1.2, 95% CI = 1.1, 1.4) of overweight/obesity relative to their active experimenting peers. As such, youth in latent classes with substance use are associated with higher BMI and weight status. Successful interventions may include school policies/programs that limit screen time use, as they were seen to have a positive effect on PA engagement and including social-influences approaches for substance use. Future research and interventions should be gender-specific as our results show that different latent classes are associated with obesity across genders.

School and class-level variations and patterns of physical activity: a multilevel analysis of Danish high school students

Background

There is limited knowledge of physical activity (PA) patterns among high school students. High schools plays an important role as context for the students, but it is uncertain to what extent schools influence student participation in PA during leisure time. The purpose of this study is to describe patterns of PA and assess variations between schools and classes in PA, in a large cohort of Danish high school students.

Methods

Self-reported cross-sectional data came from The Danish National Youth Study, comprising a total of 70,674 students attending 119 different schools and 3213 classes. Multilevel logistic regressions were applied to evaluate the association between socio-demographic variables and patterns of PA, and to assess the impact of schools and classes on PA measures.

Results

Students whose parents have achieved a lower level of education, older students and girls of perceived ethnic minority generally participated less in several forms of PA during leisure time. Substantial variations between schools were observed in terms of participation in PA at school during leisure time and in terms of use of active transportation to and from school. The school-level accounted for 9% (intra-class correlation coefficient (ICC) = 0.09 (95% CI: 0.06–0.11)) and 8% (ICC = 0.08 (95% CI: 0.07–0.11)) of the variation for participation in PA during leisure time and active transportation.

Conclusion

Overall, students whose parents achieved a lower level of education, older students and girls of perceived ethnic minority represent vulnerable groups in relation to participation in several forms of PA during leisure time. The ICCs indicate that schools, in particular, have the potential to influence participation in PA at school during leisure time and active transportation to and from school. Thus, high schools should encourage and facilitate activities aimed at engaging students in PA during leisure time as well as encourage active transportation.