Question naires were the more predominant way to evaluate PA .
Most studies showed that PA promotes a protective effect against a higher BF gain .
CONCLUSION It was concluded that PA has a protective effect against BF with differences between the genders and according to the BF marker or measurement assessed ; higher intensity PA leads to a greater effect against BF gain in both genders ; and the maintenance or increase of PA level on BF observed through analysis of change in PA level yielded more consistent findings in the relation between PA and BF
BACKGROUND Physical activity ( PA ) practice has been inversely associated to body  fat ( BF ) and recommended as a way to reduce and prevent obesity .
The objective of this study was to conduct a systematic review on the association of  PA and BF in adolescence .
Physical activity growth curves relate to adiposity in adolescents.
PURPOSE Findings from prospect i ve 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
Question naires were the more predominant way to evaluate PA .
Most studies showed that PA promotes a protective effect against a higher BF gain .
CONCLUSION It was concluded that PA has a protective effect against BF with differences between the genders and according to the BF marker or measurement assessed ; higher intensity PA leads to a greater effect against BF gain in both genders ; and the maintenance or increase of PA level on BF observed through analysis of change in PA level yielded more consistent findings in the relation between PA and BF
BACKGROUND Physical activity ( PA ) practice has been inversely associated to body  fat ( BF ) and recommended as a way to reduce and prevent obesity .
The objective of this study was to conduct a systematic review on the association of  PA and BF in adolescence .