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 ) .
A longitudinal study of sedentary behavior and overweight in adolescent girls.
The aim of this study is to examine  sedentary and light activity  in relation to overweight in adolescent girls . Adolescent girls were r and omly recruited from 36 schools participating in the Trial of Activity for Adolescent Girls ( TAAG ) . Assessment s included age , ethnicity , socioeconomic status , and body composition estimated from weight , height , and triceps skinfold .  Sedentary and light activity  was measured for 6 days using accelerometry in 6th and in 8th grade among two r and omly sample d cross-sections of girls .  Sedentary activity  increased from the 6th to 8th grade by 51.5 min/day . In the 8th grade , a significantly higher number of hours in sedentary activity for each of the 6-days of measurement were evident with higher tertiles of percent body fat ( 30 - 35 % , > 35 % fat ) ( P < 0.05 ) , but not across all increasing tertiles of BMI ( 5th to 85th , 85th to 95th , and > 95th percentiles ) . The increase in sedentary activity was observed on weekdays , but not on weekends for percent body fat tertiles . In the cohort of girls measured in both 6th and 8th grade s , the mean cross-sectional coefficient estimates were significant for percent body fat , but not BMI for sedentary and light activities . Adolescent girls from the 6th to 8th grade are shifting their time from light to more  sedentary activity as measured by accelerometers . In addition , the increase in sedentary activity is not associated with an adverse effect on BMI or percent body fat . The eventual impact of this shift to a more sedentary lifestyle on body composition and other outcomes needs to be evaluated further
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 ) .