Results Physical activity was associated with numerous health benefits .
The dose-response relations observed in observational studies indicate that the more physical activity , the greater the health benefit .
Results from experimental studies indicate that even modest amounts of physical activity can have health benefits in high-risk youngsters ( e.g. , obese ) .
Vigorous intensity activities may provide even greater benefit .
Aerobic-based activities had the greatest health benefit , other than for bone health , in which case high-impact weight bearing activities were required .
Some of the health benefits can be achieved through an average of 30 minutes per day . [
Level 2 , Grade A ] .
Background The purpose was to : 1 ) perform a systematic review of studies examining the relation between physical activity , fitness , and health in school-aged children and youth , and 2 ) make recommendations based on the findings .
A school-based exercise intervention elicits substantial bone health benefits: a 2-year randomized controlled trial in girls.
OBJECTIVE Childhood weight-bearing physical activity is recognized as an important determinant of peak bone mass , and physical activity intervention may represent a feasible strategy for primary prevention of osteoporosis . Previous school-based exercise interventions have all been of < 10 months in duration . We implemented a high-impact , circuit-based , jumping intervention ( 10 minutes , 3 times a week ) over 2 school years and compared changes in bone mineral content ( BMC ) over 20 months ( 2 school years ) in 9.9 + /- 0.6-year-old intervention girls ( N = 32 ) and controls ( 10.3 + /- 0.4 years , N = 43 ) . METHODS We measured BMC for the total body , lumbar spine , proximal femur ( and femoral neck and trochanteric subregions ) , and lean and fat mass by dual-energy radiograph absorptiometry ( Hologic QDR 4500 ) , and height , sitting height , leg length , and weight at baseline and 20 months . We assessed Tanner stage , general physical activity , and calcium intake by question naire . RESULTS Girls were Tanner breast stage 1 to 3 at baseline . There were no significant differences in baseline or 20-month change in body size or composition , average physical activity , or calcium intake between groups . There were substantially greater gains in lumbar spine ( 41.7 % vs 38.0 % ) and femoral neck ( 24.8 % vs 20.2 % ) BMC in intervention than in control girls ( P < .05 , analysis of covariance ; covariates were baseline BMC and height , change in height , physical activity , and final Tanner stage ) . CONCLUSION Three brief sessions of high-impact exercise per week implemented over 2 consecutive years within the elementary school curriculum elicited a substantial bone mineral accrual advantage in pubertal girls
Results Physical activity was associated with numerous health benefits .
The dose-response relations observed in observational studies indicate that the more physical activity , the greater the health benefit .
Results from experimental studies indicate that even modest amounts of physical activity can have health benefits in high-risk youngsters ( e.g. , obese ) .
Vigorous intensity activities may provide even greater benefit .
Aerobic-based activities had the greatest health benefit , other than for bone health , in which case high-impact weight bearing activities were required .
Some of the health benefits can be achieved through an average of 30 minutes per day . [
Level 2 , Grade A ] .
Background The purpose was to : 1 ) perform a systematic review of studies examining the relation between physical activity , fitness , and health in school-aged children and youth , and 2 ) make recommendations based on the findings .