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 ) .
Physical activity and depression in adolescents: cross-sectional findings from the ALSPAC cohort
Purpose Few studies have examined the association between physical activity ( PA ) , measured objective ly , and  adolescent depressive symptoms .  The aim of this study was to determine whether there is an association between objective measures of PA ( total PA and time spent in moderate and vigorous PA ( MVPA ) ) and adolescent depressive symptoms . Methods Data on 2,951 adolescents participating in ALSPAC were used .  Depressive symptoms were measured using the self-report Mood and Feelings Question naire ( MFQ )  ( short version ) . Measures of  PA  were based on accelerometry . The association between PA and MFQ scores was modelled using ordinal regression . Results Adolescents who were more physically active ( total PA or minutes of MVPA ) had a reduced odds of depressive symptoms [ ORadj  total PA  ( tertiles ) : medium 0.82 ( 95 % CI : 0.69 , 0.97 ) ; high 0.69 ( 95 % CI : 0.57 , 0.83 ) ] ; ORadj per 15 min MVPA  : 0.92 ( 95 % CI : 0.86 , 0.98 ) . In a multivariable model including both  total PA  and the percentage of time spent in MVPA , total PA  was associated with depressive symptoms ( ORadj  total PA  ( tertiles ) : medium 0.82 ( 95 % CI : 0.70 , 0.98 ) ; high 0.70 ( 95 % CI : 0.58 , 0.85 ) but the percentage of time spent in  MVPA  was not independently associated with depressive symptoms [ ORadj MVPA ( tertiles ) medium 1.05 ( 95 % CI : 0.88 , 1.24 ) , high 0.91 ( 95 % CI : 0.77 , 1.09 ) ] . Conclusions The total amount of PA undertaken was associated with  adolescent depressive symptoms , but the amount of time spent in MVPA , once total PA was accounted for , was not . If confirmed in longitudinal studies and r and omised controlled trials , this would have important implication s for public health messages
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 ) .