Overall , total PA was favourably associated with physical , psychological/social , and cognitive health indicators .
Relationships were more consistent and robust for higher ( e.g. , MVPA ) versus lower ( e.g. , LPA ) intensity PA .
All patterns of activity ( sporadic , bouts , continuous ) provided benefit .
LPA was favourably associated with cardiometabolic biomarkers ; data were scarce for other outcomes .
These findings continue to support the importance of at least 60 min/day of MVPA for disease prevention and health promotion in children and youth , but also highlight the potential benefits of LPA and total PA .
Moderate-to-vigorous physical activity ( MVPA ) is essential for disease prevention and health promotion .
Emerging evidence suggests other intensities of physical activity ( PA ) , including light-intensity activity ( LPA ) , may also be important , but there has been no rigorous evaluation of the evidence .
The purpose of this systematic review was to examine the relationships between objective ly measured PA ( total and all intensities ) and health indicators in school-aged children and youth .
Online data bases were search ed for peer- review ed studies that met the a priori inclusion criteria : population ( apparently healthy , aged 5 - 17 years ) , intervention/exposure/comparator ( volumes , duration s , frequencies , intensities , and patterns of objective ly measured PA ) , and outcome ( body composition , cardiometabolic biomarkers , physical fitness , behavioural conduct/pro-social behaviour , cognition/academic achievement , quality of life/well-being , harms , bone health , motor skill development , psychological distress , self-esteem ) .
Bidirectional cross-sectional and prospective associations between physical activity and body composition in adolescence: Birth cohort study
Abstract The aim of this study was to investigate the cross-sectional and prospect i ve associations between physical activity and  body composition in adolescence . This is a prospect i ve study , including 4,103 adolescents belonging to the Pelotas ( Brazil ) 1993 birth cohort , who were followed up at the mean ages of 11.3 and 14.7 years . Sub sample analyses included 511 individuals with accelerometry and deuterium dilution data at 13.3 years .  Sum of skinfolds at age 11.3 years was highly correlated with skinfolds at age 14.7 years ( rho = 0.74 , P < 0.001 ) . More than 85 % of participants remained in the same quintile or changed by not more than one quintile during the 3.4 year period .  Tracking of physical activity  was considerably lower , although still significant ; the correlation was 0.24 ( P < 0.001 ) and 61.4 % of the adolescents moved one or less quintiles . In fully-adjusted models , no significant cross-sectional or longitudinal associations were found between physical activity and body composition , neither in boys nor in girls . These null results were confirmed in the 511 individuals with accelerometry and deuterium data . We provide evidence of  tracking of physical activity and particularly body composition during adolescence . Our results do not support the hypothesis that physical activity and fatness are strongly related in adolescents
Overall , total PA was favourably associated with physical , psychological/social , and cognitive health indicators .
Relationships were more consistent and robust for higher ( e.g. , MVPA ) versus lower ( e.g. , LPA ) intensity PA .
All patterns of activity ( sporadic , bouts , continuous ) provided benefit .
LPA was favourably associated with cardiometabolic biomarkers ; data were scarce for other outcomes .
These findings continue to support the importance of at least 60 min/day of MVPA for disease prevention and health promotion in children and youth , but also highlight the potential benefits of LPA and total PA .
Moderate-to-vigorous physical activity ( MVPA ) is essential for disease prevention and health promotion .
Emerging evidence suggests other intensities of physical activity ( PA ) , including light-intensity activity ( LPA ) , may also be important , but there has been no rigorous evaluation of the evidence .
The purpose of this systematic review was to examine the relationships between objective ly measured PA ( total and all intensities ) and health indicators in school-aged children and youth .
Online data bases were search ed for peer- review ed studies that met the a priori inclusion criteria : population ( apparently healthy , aged 5 - 17 years ) , intervention/exposure/comparator ( volumes , duration s , frequencies , intensities , and patterns of objective ly measured PA ) , and outcome ( body composition , cardiometabolic biomarkers , physical fitness , behavioural conduct/pro-social behaviour , cognition/academic achievement , quality of life/well-being , harms , bone health , motor skill development , psychological distress , self-esteem ) .