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 ) .
Effects of Changes in Adiposity and Physical Activity on Preadolescent Insulin Resistance: The Australian LOOK Longitudinal Study
Background In a previous longitudinal analysis of our cohort as 8 to 10 year-olds , insulin resistance ( IR ) increased with age , but was not modified by changes in percent body fat ( % BF ) , and was only responsive to changes in physical activity ( PA ) in boys . We aim ed to determine whether these responses persisted as the children approached adolescence . Methods In this prospect i ve cohort study , 256 boys and 278 girls were assessed at ages 8 , 10 and 12 years for fasting blood glucose and insulin , % BF ( dual energy X-ray absorptiometry ) ; PA ( 7-day pedometers ) , fitness ( multistage run ) ; and pubertal development ( Tanner stage ) . Results From age 8 to 12 years , the median homeostatic model of IR ( HOMA-IR ) doubled in boys and increased 250 % in girls . By age 12 , 23 % of boys and 31 % of girls had elevated IR , as indicated by HOMA-IR greater than 3 . Longitudinal relationships , with important adjustments for covariates body weight , PA , % BF , Tanner score and socioeconomic status showed that , on average , for every 1 unit reduction of % BF , HOMA-IR was lowered by 2.2 % ( 95 % CI 0.04–4 ) in girls and 1.6 % ( 95 % CI 0–3.2 ) in boys . Furthermore , in boys but not girls , HOMA-IR was decreased by 3.5 % ( 95%CI 0.5–6.5 ) if PA was increased by 2100 steps/day . Conclusion Evidence that a quarter of our apparently healthy 12 year-old Australians possessed elevated IR suggests that community-based education and prevention strategies may be warranted . Responsiveness of IR to changes in % BF in both sexes during late preadolescence and to changes in PA in the boys provides a specific basis for targeting elevated IR . That body weight was a strong covariate of IR , independent of % BF , points to the importance of adjusting for weight in correctly assessing these relationships in growing children
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 ) .