Search

Recommendations for physical activity (PA) typically focus on frequency, intensity, duration, and type, but timing (chrono-exercise) is also important. The objective of this study is to describe when children are active on school and weekend days and explore PA timing across sex and body mass index (BMI) categories. 359 children (53% male), aged 9.6 (0.9) y, were categorized as normal weight (≥-1 standard deviations (SD) and <1SD; n = 193), overweight (≥1SD and <2SD; n = 80), or obese (≥2SD; n = 86) using WHO BMIz. Moderate-to-vigorous PA (MVPA) was assessed using ActiGraph LS-7164. The results are described as Mean(SD). ANOVA evaluated MVPA across sexes and BMI categories. Normal weight boys were more active than boys with obesity on school (Δ20.33 min; p < 0.001) and weekend days (Δ15.04 min; p < 0.05). On school days, significant differences existed between 9:00 h-11:00 h and 12:00 h-14:00 h (p < 0.017), while on weekends, smaller differences existed throughout the day. Girls' MVPA was similar across BMI categories, on all days (p > 0.05). On school days, 12:00 h-13:00 h represented the most active hour for all participants (~14% total daily MVPA). Peak weekend MVPA was distributed across multiple hours. Differences in MVPA timing emerged on school-days and weekends. Timing may be important when examining the nuances of MVPA in relation to sex and bodyweight in children. [ABSTRACT FROM AUTHOR]

Background: Behavioral trajectories from childhood to adolescence may differ and are poorly understood. The authors estimated the trajectories of moderate to vigorous physical activity (MVPA), screen time, and sleep duration during this period, by sex and initial weight status. Methods: Data from Quebec Adiposity and Lifestyle Investigation in Youth, an ongoing cohort study in Canada on the natural history of obesity, were used. Participants predisposed to obesity attended baseline (8–10 y old, n = 630) and follow-up visits 2 years (n = 564) and 7 years (n = 359) after baseline. Participants with completed self-reported and accelerometer-based data were included in the analyses (n = 191, 353, and 240 for MVPA, screen time, and sleep, respectively). The authors performed group-based trajectory analyses and multinomial logistic regression models. Results: Two MVPA, 3 screen time, and 2 sleep trajectories were identified. Girls were more likely than boys to belong to trajectory with lower MVPA means (odds ratio [OR] = 6.45; 95% confidence interval [CI], 3.08 to 13.49), yet less likely to belong to the trajectory with higher screen time (OR = 0.47; 95% CI, 0.23 to 0.97) and lower sleep duration (OR = 0.46; 95% CI, 0.27 to 0.78). Overweight or obesity at baseline was associated with a greater likelihood of belonging to the trajectory with lower MVPA (OR = 10.99; 95% CI, 1.31 to 91.14) and higher screen time (OR = 2.01; 95% CI, 1.04 to 4.06), respectively. Conclusions: It appears to be gender- and weight-based determinants of behavioral trajectories in this sample. These results may provide guidance for interventions in similar populations. [ABSTRACT FROM AUTHOR]

Estimate the shape and number of cardiorespiratory fitness (CRF) trajectories from childhood to adolescence; and verify whether CRF trajectory membership can be predicted by sex, biological maturation, body weight, body composition and physical activity (PA) in childhood. Data from QUALITY were used. Participants attended baseline (8–10 y old, n = 630) and follow-ups 2 years (n = 564) and 7 years (n = 359) after baseline. Group-based trajectory analysis for relative peak oxygen consumption (VO2peak, ml·kg−1·min−1) was performed. A multinomial logistic regression model was used to estimate the associations between baseline predictors and trajectory membership. Mean age of the 454 participants was 9.7 ± 0.9 years at baseline. Three distinct VO2peak trajectories were identified and all tended to decrease. They were labelled according to the starting point and slope. High-Decreasers were mostly boys, had lower body weight and fat-free mass index and higher PA levels at baseline (p < 0.05). Female sex and higher weight were associated with higher odds of being classified in the Low-Decreaser trajectory (OR = 74.03, 95%CI = 27.06–202.54; OR = 1.48, 95%CI = 1.36–1.60). Those with higher PA were less likely to be Low-Decreasers (OR = 0.96, 95%CI = 0.94–0.97). Sex, body weight and PA in childhood are important influencing factors of VO2peak (ml·kg−1·min−1) trajectories across adolescence. [ABSTRACT FROM AUTHOR]

Background: We compared the relation between neighborhood features and moderate to vigorous physical activity (MVPA) using linear regression analysis and the more novel compositional data analysis (CoDA). Compositional data analysis allows us to take the time children allocate to different movement behaviours during a 24-hour time period into account. Methodology: Data from youth participants (n = 409) in the QUALITY (QUebec Adipose and Lifestyle InvesTigation in Youth) cohort were included. Time spent in MVPA, light physical activity, sedentary behavior, and sleep ("24-hour movement behaviours") was measured using accelerometers. Neighborhood data were collected using a geographic information system and through direct observation. In CoDA models, we used orthogonal logratio coordinates, which allows for the association of neighbourhood walkability with MVPA to be estimated with respect to the average composition of all other behaviours within a 24-hour time frame. In baseline linear regression models, MVPA was regressed cross-sectionally on neighborhood walkability. All models were stratified by sex, and controlled for BMI z-scores, pubertal development, seasonal variation, parental education, and neighbourhood safety. Results: Based on CoDA, girls who lived in more walkable neighborhoods had 10% higher daily MVPA (95% CI: 2%, 19%), taking into account all other movement behaviours. Based on linear regression, girls who resided in more walkable neighborhoods engaged in 4.2 (95% confidence interval [CI]: 1.2, 6.6) more minutes of MVPA per day on average than girls residing in less walkable neighborhoods. Conclusions: Unlike with traditional linear models, all movement behaviours were included in a single model using CoDA, allowing for a more complete picture of the strength and direction of the association between neighbourhood Walkability and MVPA. Application of CoDA to investigate determinants of physical activity provides additional insight into potential mechanisms and the ways in which people allocate their time. [ABSTRACT FROM AUTHOR]

Summary: Background: The 24‐hour movement guidelines provide recommendations for physical activity, screen time and sleep duration for children. Objectives: Describe adherence to the guidelines and their cross‐sectional and longitudinal associations with adiposity from childhood to adolescence. Methods: Data are from the QUALITY Cohort. Children were followed at 8 to 10 years (childhood; n = 630), 10 to 12 years (early adolescence; n = 564) and 15 to 17 years (adolescence; n = 377). Physical activity, screen time, and sleep duration were measured by accelerometry and questionnaires. Body mass index z‐scores (zBMI), waist circumference, waist‐to‐height ratio and percent body fat were based on clinical measurements. Multiple linear regressions estimated associations. Results: In childhood, early adolescence and adolescence, 14%, 6%, and 0% of participants met the 24‐hour movement guidelines, respectively. Meeting fewer guideline components was cross‐sectionally associated with higher adiposity at each visit. Meeting fewer guideline components in childhood was longitudinally associated with higher adiposity at later visits. For example, those meeting none of the guideline components (vs all) in childhood had a 1.66 SD (95% CI: 0.42, 2.89) higher zBMI in early adolescence. Conclusion: Few participants met the guidelines. Not meeting the guidelines in childhood is associated with higher adiposity 2 and 7 years later. Interventions are needed to increase adherence to the 24‐hour movement guidelines across childhood and adolescence. [ABSTRACT FROM AUTHOR]

Background: We investigated the population trajectory of leisure time physical activity (LTPA) in adults age 18 to 60 y (n = 881), who were recruited in 1981 for the Canada Fitness Survey and followed-up through the Campbell's Survey on Well-Being (1988) and the Physical Activity Longitudinal Study (2002/04). Methods: Data on involvement in LTPA were collected by questionnaire and used to estimate average daily energy expenditure (EE) (kcal · kg-1 · d-1) during leisure time. Growth trajectory modeling was used to describe the overall population trajectory of LTPA and the extent to which average trajectories varied between sub-groups defined by age, sex, and education. Results: The population trajectory of LTPA over time was modified by baseline age, but not by sex or by level of education. Disparities in LTPA related to sex and education persisted over two decades. Conclusion: This longitudinal investigation improves our understanding of the processes underlying patterns of LTPA in adults. [ABSTRACT FROM AUTHOR]

To estimate the shape and number of mechanical efficiency (ME) trajectories from childhood to adolescence; and verify whether ME trajectory membership can be predicted by sex, biological maturation, body weight, body composition and physical activity (PA) in childhood. Data from QUALITY, an ongoing cohort study on the natural history of obesity, were used. Participants attended a baseline visit (8–10 years, n = 630) and follow-up visits two years (n = 564), and seven years (n = 377) later. ME was assessed by an incremental cycling test at 50w (ME 50w , %) and at VO 2peak (ME VO2peak , %). Group-based trajectory analysis for ME and a logistic regression were performed. Mean age of the 454 participants (boys = 54%) was 9.7 ± 0.9 years at baseline. Two distinct ME 50w trajectories were identified and all tended to decrease. No distinct trajectories emerged for ME VO2peak ; average ME VO2peak increased over time. Thus, the difference between ME VO2peak (∆) at baseline and follow-up was calculated for correlation analysis. Trajectory groups were labeled "Low-Decreaser" and "High-Decreaser" (Reference) for ME 50w , describing the starting point and slope. High-Decreasers were mostly prepubertal girls, had lower body weight and fat free mass index, lower PA and lower VO 2peak at baseline (χ2or t -test, p < 0.05). Girls were less likely to be Low-Decreasers (OR = 0.56, 95%CI = 0.42–0.74), while having overweight/obesity predicted a greater likelihood of classification in the Low-Decreaser trajectory (OR = 2.38, 95%CI = 1.16–4.88). Those with higher PA were more likely to be Low-Decreasers (OR = 1.02, 95%CI = 1.01–1.04). Finally, concerning ME VO2peak , sex, biological maturation, body weight, zBMI, fat free mass index, PA and VO 2peak were positively correlated with ∆ ME VO2peak. We found evidence that excess weight at baseline predicts low levels of ME in childhood and adolescence. Additionally, higher PA at baseline is not related to higher ME 50w levels. More research is needed to identify different approaches to explore this measure in transition to adulthood. • Trajectories of mechanical efficiency of cycling at 50 W decreased thru the adolescence. • Mean values of mechanical efficiency at VO 2peak increased throughout the adolescence. • Excess weight predicts low levels of mechanical efficiency in childhood and adolescence. • Higher physical activity at baseline is not related to higher mechanical efficiency levels. [ABSTRACT FROM AUTHOR]

This study applied socioecological and cumulative risk exposure frameworks to test the hypotheses that 1) the experience of poverty is associated with feeling less safe at school, and 2) feeling less safe is associated with engaging in poorer weight-related behaviors, as well as an increased probability of being overweight or obese. Data were from the ongoing Québec Longitudinal Study of Child Development, initiated in 1998 with a population-based cohort of 2,120 Québec (Canada) infants 5 months of age and their parent or primary caregiver. Measures of youths' (age, 13 years) self-reported feelings of safety, screen time, physical activity, and objectively assessed not overweight/obese (70%), overweight (22%), and obese (8%) weight status were collected in 2011. Family poverty trajectory from birth was assessed by using latent growth modeling. As hypothesized, exposure to poverty was associated with feeling less safe at school and, in turn, with an increased probability of being overweight or obese. The association was most pronounced for youths who experienced chronic poverty. Compared with youths who experienced no poverty and felt unsafe, those who experienced chronic poverty and felt unsafe were nearly 18% more likely to be obese (9.2% vs. 11.2%). Although feeling unsafe was associated with screen time, screen time did not predict weight status. [ABSTRACT FROM AUTHOR]

Background: Adolescent physical activity (PA) levels track into adulthood. However it is not known if type of PA participated in during adolescence is associated with PA levels later in life. We aimed to identify natural groupings of types of PA and to assess whether number of years participating in these different groupings during adolescence is related to PA level in early adulthood. Methods: 673 adolescents in Montreal, Canada, age 12-13 years at baseline (54 % female), reported participation in 29 physical activities every 3 months over 5 years (1999-2005). They also reported their PA level at age 24 years (2011-12). PA groupings among the 29 physical activities were identified using factor analysis. The association between number of years participating in each grouping during adolescence and PA level at age 24 was estimated using linear regression within a general estimating equation framework. Results: Three PA groupings were identified: "sports", "fitness and dance", and "running". There was a positive linear relationship between number of years participating in sports and running in adolescence and PA level at age 24 years (β (95 % confidence interval) = 0.09 (0.04-0.15); 0.08 (0.01-0.15), respectively). There was no relationship between fitness and dance in adolescence and PA level at age 24. Conclusions: The association between PA participation in adolescence and PA levels in young adulthood may be specific to certain PA types and to consistency of participation during adolescence. Results suggest that efforts to establish the habit of participation in sports and running in adolescence may promote higher PA levels in adulthood. [ABSTRACT FROM AUTHOR]

Purpose:Identification of factors that relate to physical activity behavior in children at higher risk for weight problems—namely, children with obese parents—is key to informing the development of effective interventions to promote physical activity and reduce obesity. The purpose of our study was to examine children's perceptions of parental social support for physical activity and the associations between these perceptions and health-enhancing physical activity behavior. Our specific objectives were to: (a) compare perceptions of parental support in children across gender and weight status; (b) compare perceptions of support across source (mother, father) and type (tangible, intangible) in normal-weight and overweight girls and boys; and (c) examine the associations between perceptions of parental support and moderate-to-vigorous physical activity (MVPA) behavior.Method:We used data collected from the Quebec Adiposity and Lifestyle Investigation in Youth, an investigation of Caucasian children with at least 1 obese biological parent. We included in the analyses children (n = 560,Mage = 9.6 years, 55% boys, 41% overweight/obese) with data on parental support assessed using a self-report questionnaire and data on MVPA assessed using accelerometers.Results:Multivariate analyses of variance indicated that perceptions of support differed by children's gender and weight status. Paired-samplesttests showed that children reported more intangible than tangible support. Regression analyses demonstrated that perceptions of paternal tangible support were positively related to MVPA in normal-weight girls, but only a small amount of variance was explained.Conclusions:Children's gender and weight status need to be considered when studying parental support for physical activity. Further, type and source of support should be differentiated in future research. [ABSTRACT FROM PUBLISHER]

Abstract: Purpose: Findings from prospective studies on associations between physical activity and adiposity among youth are inconsistent. Our aim was to describe physical activity trajectories during secondary school and examine the association with change in adiposity in youth. Methods: Physical activity was measured in 20 survey cycles from 1999 to 2005; anthropometrics were measured in survey cycles 1, 12, and 19. Individual growth curves modeling moderate-to-vigorous physical activity (MVPA) and vigorous physical activity (VPA) were estimated. Estimates of initial level and rate of decline in MVPA and VPA bouts per week were included as potential predictors of body fat% and body mass index using age- and sex-specific linear regression. Results: Complete data were available for 840 and 760 adolescents aged 12–13 years at baseline, followed from survey cycles 1–12 and 12–19, respectively. Among girls, yearly declines of one MVPA and one VPA bout per week during earlier adolescence were associated with increases of 0.19 (95% confidence interval [CI], 0.02–0.36) and 0.47 (95% CI, 0.015–0.92) units of body fat%, respectively. In boys, a yearly decline of one MVPA bout per week was associated with an increase of 0.38 (95% CI, 0.05–0.70) units of body fat% during later adolescence. Conclusions: Obesity prevention programs should include strategies to prevent declines in physical activity. [Copyright &y& Elsevier]

OBJECTIVE - To describe the associations among moderate-to-vigorous physical activity (MVPA), fitness, sedentary behavior (SB), and insulin sensitivity (IS). RESEARCHDESIGNANDMETHODS - Data were drawn from the baseline assessment of the QUALITY cohort, which included 630 white youth (aged 8-10 years at recruitment), with at least one obese biological parent. IS was measured by two fasting indices (insulin, homeostasis model assessment of insulin resistance) and an oral glucose tolerance test (OGTT)-based index (Matsuda IS index [Matsuda-ISI]). Fitness was measured by Vo2peak; percent fat mass (PFM) was measured by dual-energy X-ray absorptiometry; 7-day MVPA wasmeasured with accelerometry. SB indicators included average hours daily of self-report screen time (SBst), and average minutes daily at ,100 counts/min from accelerometry (SBacc). Multivariable linear regression models were adjusted for age, sex, season, and puberty. RESULTS - MVPA and SBacc were independently associated with IS, but this was no longer statistically significant after accounting for PFM. SBst was negatively associated with IS in girls only, even after controlling for physical activity (PA), fitness, and adiposity; for each additional hour of SBst daily, IS decreased by 4.6-5.6% across all IS indices. Fitness was positively associated with IS (measured by Matsuda-ISI) after accounting for PA, SB, and PFM; for every 1 unit increase in VO2peak, Matsuda-ISI increased by approximately 1.0% (P < 0.05). CONCLUSIONS - In children with an obese parent, PA and SBacc are associated with IS, but this association is mediated by adiposity. SBst is negatively associated with IS in girls, beyond its known impact on adiposity. Finally, fitness is independently associated with better IS measured by OGTT. [ABSTRACT FROM AUTHOR]

Purpose. The association between physical activity (PA) and inflammation has been established in adults, yet little is known about this relationship in youth. This study examined the relationship between vigorous PA and C-reactive protein (CRP) in adolescents. Methods. Data were available for 1 520 adolescents, aged 13 and 16 years, in a province-wide survey of a representative sample of youth in Québec, Canada. Participants completed questionnaires assessing VPA, pubertal stage, body image, and health problems; they provided a fasting blood sample for CRP; and they had height and weight measured. Results. In sex-specific multivariable logistic regression models, VPA was protective of elevated CRP in boys (OR=0.60, 95%CI=0.37-0.99) independent of weight status, pubertal stage, anti-inflammatory/antibiotic medication, and smoking. CRP and physical activity were not related in girls (OR=1.12, 95%CI=0.69-1.82). Conclusions. In addition to many known health benefits of VPA, the current findings provide evidence that VPA may protect against low-grade systemic inflammation in boys. These data provide further support for the importance of promoting healthy PA levels in youth. [ABSTRACT FROM AUTHOR]

The article presents a study that describes the opportunities for student physical activity (PA) in elementary schools in the U.S. The purpose of this study is to identify the factors associated with schools offering more PA opportunities. In this study, questionnaires were completed by school principals and physical education teachers in 277 elementary schools in metropolitan Montreal. Study shows that addressing barriers related to resources and access to sports facilities may help lessen disparities between schools in opportunities for students to engage in PA.

Objective: To determine whether lifestyle habits and dietary factors at age 8-10 years predict the development of metabolically unhealthy obesity 2 years later among children who were previously metabolically healthy obese.Study Design: The QUebec Adipose and Lifestyle InvesTigation in Youth cohort comprises 630 youth with a parental history of obesity. Metabolically healthy obesity and metabolically unhealthy obesity were defined using cut-offs for the components of pediatric metabolic syndrome. Dietary factors, physical activity, fitness, sedentary behavior, screen time, and sleep duration were measured. Multivariable logistic regressions were used to examine associations.Results: At baseline, 48 participants with metabolically healthy obesity were identified; 2 years later, 19 became metabolically unhealthy obese and 29 remained metabolically healthy obese. Every additional daily portion of fruits and vegetables decreased the risk of converting to metabolically unhealthy obesity by 39% (OR 0.61, 95% CI 0.40-0.94). Cumulating more hours of screen time and diets high in saturated fat and sugar-sweetened beverages and low in protein were associated with a tendency to develop metabolically unhealthy obesity.Conclusions: Fruit and vegetable intake and possibly screen time, saturated fat, sugar-sweetened beverages, and protein intake may be important targets for the prevention of cardiometabolic complications in obese children.Trial Registration: ClinicalTrials.gov: NCT03356262. [ABSTRACT FROM AUTHOR]

The objective of this study was to determine whether the relationship between income and leisure-time physical activity (LTPA) persists after accounting for a person's utilitarian PA (all non-LTPA), sociodemographic characteristics and transportation PA. Data were from eight cycles (1999-2014) of the nationally representative samples of the US adult population from the National Health and Nutrition Examination Survey (n = 35,239). Whether the poverty income ratio (0-1.3, 1.3-1.86, 1.86+ [reference]) was associated with minutes of LTPA (moderate, vigorous) after stratifying for utilitarian PA (sedentary, light, moderate, and vigorous) was assessed in multiple linear regressions adjusted for age, sex, race, education, marital status, weight status, hours worked, and minutes of transportation-related PA in the past week. Likelihood of meeting national physical activity recommendations was also assessed in multiple logistic regressions adjusting for the covariates described. For both sedentary and light utilitarian PA levels, compared to the reference, persons living in households of the lowest poverty income ratio were consistently associated with approximately 17-30 less minutes of moderate LTPA minutes per week, and 20-25 less minutes of vigorous LTPA across all survey cycles. Compared to the reference, the likelihood of meeting national PA recommendations was approximately 31-55% less for these households. The known association between lower income and lower LTPA persist, but is the most persistent and consistent for those with less active utilitarian (such as sedentary) lifestyles. Interventions aimed at increasing LTPA among people with low income and sedentary utilitarian lifestyles whether or not they are in the workforce are particularly needed. [ABSTRACT FROM AUTHOR]

Purpose: We investigated whether type of physical activity (PA) (sports, running, and fitness/dance) engaged in during adolescence is associated with body composition in late adolescence or early adulthood. Methods: Data were drawn from 631 participants in the Nicotine Dependence in Teens study, a prospective investigation of students ages 12-13 yr at inception. Self-report PA data were collected at baseline, in grade 7, and every 3-4 months thereafter during the 5 yr of high school (1999-2005). Anthropometric indicators (height, weight, waist circumference, triceps, and subscapular skinfold thickness) were measured at ages 12, 16, and 24 yr. On the basis of prior exploratory factor analysis, PA was categorized into one of three types (sports, running, and fitness/dance). Regression models estimated the association between number of years participating in each PA type (0-5 yr) during high school and body composition measures in later adolescence or early adulthood. Results: In multivariable models accounting for age, sex, and parent education, more number of years participating in running during adolescence was associated with lower body mass index, waist circumference, and skinfold thickness in later adolescence and early adulthood (all P < 0.01). This association was no longer apparent in models that accounted for body composition at age 12 yr. The number of years participating in sports was positively associated with body mass index in early adulthood (P = 0.02), but fitness/dance was not statistically significantly associated with any outcome. Conclusion: Sustaining participation in running, but not in other PA types, during adolescence was related to lower body composition in later adolescence and adulthood. However, more research is needed to determine whether this association is attributable to a relationship between PA and body composition in early adolescence. [ABSTRACT FROM AUTHOR]

Background The operationalization of opportunities for physical activity (PA) in parks has not been studied extensively. Objectives To explore associations between park types, PA and adiposity in youth. Methods Data were from an ongoing cohort study in children at risk of obesity. Data were collected in 512 participants (2005–2008). Analyses were restricted to 380 participants living within ≥ 1000 m of ≥ 1 park (n parks = 576). Park types were identified using principal component and cluster analyses. Linear and logistic regressions were used to explore associations between park types, and PA and adiposity. The reference category was children living near smaller-sized parks with no team PA features. Results Nine park types were identified. Compared to the reference group, children living near esthetically pleasing parks with few team sports installations reported more 15-minute bouts of PA/week (bouts of PA) ( β = 5.2 [90% CI: 2.3; 8.1]) and variety of PA (1.6 [0.1; 3.1]), and had less % truncal fat (− 3.4 [− 6.4; − 0.5]). Children living near parks that were low on safety items with cycling infrastructure reported more bouts of PA (2.2 [0; 4.3]) and variety of PA (0; 2.2]). Children living near parks with a variety of PA installations reported more bouts of PA (2.5 [0.2; 4.7]) and variety of PA (1.4 [0.2; 2.5]). Children living near parks that had team sports and pool features reported more bouts of PA (2.5 [0.4; 4.7]). No significant associations were found for objectively-measured PA. Conclusion Parks that emphasize unstructured activities may increase self-reported PA and be associated with less % truncal fat among youth at risk of obesity. [ABSTRACT FROM AUTHOR]

Abstract: Objective: The objective of this study is to examine depressive symptom trajectories during adolescence as predictors of physical activity (PA) in young adulthood. Methods: Adolescents residing in Montreal, Canada (n=860) reported their depressive symptoms every 3–4months during high school in 20 data collections. Three years later, participants reported engaging in moderate and vigorous intensity PA and team sports participation. Trajectories of depressive symptoms were estimated using latent growth modeling and examined as predictors of PA outcomes. Results: Three depression symptom trajectory groups were identified during adolescence: low and declining depressive symptom scores (group 1; 37.8%); moderate and stable depressive symptom scores (group 2; 41.6%); and high increasing depressive symptom scores (group 3; 20.6%). In multivariable analyses, group 2 and group 3 participated in less moderate-intensity PA and were less likely to participate in team sports compared to group 1. Conclusions: The importance of examining intensity and type of PA as outcomes of depressive symptoms is highlighted. Targeted approaches are needed to encourage adolescents with moderate to high depression symptoms to engage in PA and team sports to improve their health and well-being. [Copyright &y& Elsevier]

Abstract: Purpose: The objectives of this study were to assess (1) the longitudinal associations of past moderate-to-vigorous physical activity (MVPA) and involvement in team sports during secondary school with depressive symptoms in early adulthood, and (2) the cross-sectional associations of current MVPA and involvement in team sports with depressive symptoms during young adulthood. Methods: Data were drawn from the Nicotine Dependence in Teens study, which is an ongoing prospective cohort study of 1293 adolescents aged 12–13 years at baseline (52% female). Data analyses involved latent growth curve modeling and multiple hierarchical linear regression models. Results: Current MVPA (β = −0.12), but not past MVPA, participation was significantly negatively related to depressive symptoms during young adulthood (P < .05). Both current and past involvement in team sports were significantly negatively related to depressive symptoms (β ≥ −0.09; P < .05); however, these associations were no longer significant (P = .08) when covariates were controlled for. Conclusions: Findings provide insight about the unique associations between the timing and type of physical activity and depressive symptoms, suggesting that physical activity within team sport contexts should be encouraged so that young adults may experience less depressive symptoms. [Copyright &y& Elsevier]

Extracurricular sport has been a valued educational investment to promote both physical and mental health in children and adolescents. Few longitudinal studies have tested whether extracurricular sport is associated with inattentive/hyperactive symptoms. Using a prospective-longitudinal birth cohort of 758 girls and 733 boys, we examined the prospective relationship between consistent middle childhood participation in extracurricular sport and subsequent ADHD symptoms. We hypothesized that engaging in extracurricular sport will promote reductions in symptoms. As a predictor, mothers reported on whether the child participated in sport or organized physical activities with a coach/instructor at ages 6, 7, 8, and 10 years. Developmental trajectories of the sport predictor, from ages 6 to 10 years, were generated using longitudinal latent class analysis. At age 12 years, sixth grade teachers reported on child ADHD symptom outcomes observed in the school setting over the last 6 months. ADHD symptoms were linearly regressed on trajectories of participation in organized sport in boys and girls, while controlling for pre-existing child and family characteristics. For girls, consistent participation in organized sport significantly predicted lower subsequent ADHD symptoms, compared with girls with low-inconsistent participation (unstandardized B = 0.07, p ≤ .05, 95% CI, 0.01-0.14). Early sustained middle childhood involvement in organized sport seems beneficial for the subsequent behavioral development of girls but no associations were found for boys. Middle childhood participation in structured venues that demand physical skill and effort with a coach or instructor may thus represent a valuable policy strategy to promote this aspect of behavioral development for girls. [ABSTRACT FROM AUTHOR]