There was some evidence that school-based physical activity interventions had a positive impact on four of the nine outcome measures .
Specifically positive effects were observed for duration of physical activity , television viewing , VO2 max , and blood cholesterol .
Generally , school-based interventions had little effect on physical activity rates , systolic and diastolic blood pressure , BMI , and pulse rate .
At a minimum , a combination of printed educational material s and changes to the school curriculum that promote physical activity result ed in positive effects .
Few changes in outcomes were observed in this up date with the exception of blood cholesterol and physical activity rates .
For example blood cholesterol was no longer positively impacted upon by school-based physical activity interventions .
The evidence suggests the ongoing implementation of school-based physical activity interventions at this time , given the positive effects on behavior and one physical health status measure .
BACKGROUND The World Health Organization ( WHO ) estimates that 1.9 million deaths worldwide are attributable to physical inactivity and at least 2.6 million deaths are a result of being overweight or obese .
In addition , WHO estimates that physical inactivity causes 10 % to 16 % of cases each of breast cancer , colon , and rectal cancers as well as type 2 diabetes , and 22 % of coronary heart disease and the burden of these and other chronic diseases has rapidly increased in recent decades .
OBJECTIVES The purpose of this systematic review was to summarize the evidence of the effectiveness of school-based interventions in promoting physical activity and fitness in children and adolescents .
Bone mass and structure are enhanced following a 2-year randomized controlled trial of exercise in prepubertal boys.
Exercise during growth has a positive influence on bone mineral accrual , yet little is known about how bone geometry and strength adapt to loading during growth . Our primary objective was to compare changes in proximal femur bone geometry and strength between 31 prepubertal ( Tanner Stage 1 ) boys who participated in a school-based , high-impact circuit intervention ( 12 min , three times a week ) for 20 months and 33 maturity-matched controls . Our secondary objective was to compare changes in total body ( TB ) , proximal femur ( PF ) , and lumbar spine ( LS ) bone mineral content ( BMC ) and bone area ( BA ) in these groups . We assessed geometric variables and bone strength at the narrow neck ( NN ) , intertrochanteric ( TR ) region , and femoral shaft regions by applying the Hip Structure Analysis program to proximal femur dual energy X-ray absorptiometry scans ( DXA , Hologic QDR 4500 ) . Further , we assessed total body , lumbar spine , and proximal femur BMC and BA by DXA and derived total body lean mass and fat mass from total body scans . Intervention ( 10.2 + /- 0.5 years ) and control boys ( 10.1 + /- 0.5 years ) had similar baseline height ( 140.8 vs. 141.3 cm ) and weight ( 36.9 vs. 35.4 kg ) , and average 20-month physical activity scores ( Physical Activity Question naire for Children , PAQ-C ) and calcium intakes ( 861 vs. 852 mg/day , food frequency question naire ) . Twenty-month height and weight changes were not significantly different between groups ; lean mass changed more ( P < 0.05 ) in intervention boys ( 22.8 % ) than control boys ( 18.6 % ) . At the NN region , intervention boys had greater bone expansion on both the periosteal ( + 2.6 % , P = 0.1 ) and endosteal ( + 2.7 % , P = 0.2 ) surfaces , result ing in significantly greater changes in section modulus ( bone bending strength ) ( + 7.5 % , P = 0.02 , ANCOVA , adjusting for height change , final Tanner Stage , and baseline bone values ) . Changes at the intertrochanteric and femoral shaft regions were not significantly different between groups . Femoral neck ( FN ) BMC changes were significantly greater in intervention boys ( + 4.3 % , P < 0.01 ) ; changes in BA and BMC for other regions were not significantly different between groups . In summary , a school-based , high-impact exercise intervention implemented three times a week for 12 min is an effective strategy for site-specific gains in bone strength at the narrow neck region of the proximal femur
There was some evidence that school-based physical activity interventions had a positive impact on four of the nine outcome measures .
Specifically positive effects were observed for duration of physical activity , television viewing , VO2 max , and blood cholesterol .
Generally , school-based interventions had little effect on physical activity rates , systolic and diastolic blood pressure , BMI , and pulse rate .
At a minimum , a combination of printed educational material s and changes to the school curriculum that promote physical activity result ed in positive effects .
Few changes in outcomes were observed in this up date with the exception of blood cholesterol and physical activity rates .
For example blood cholesterol was no longer positively impacted upon by school-based physical activity interventions .
The evidence suggests the ongoing implementation of school-based physical activity interventions at this time , given the positive effects on behavior and one physical health status measure .
BACKGROUND The World Health Organization ( WHO ) estimates that 1.9 million deaths worldwide are attributable to physical inactivity and at least 2.6 million deaths are a result of being overweight or obese .
In addition , WHO estimates that physical inactivity causes 10 % to 16 % of cases each of breast cancer , colon , and rectal cancers as well as type 2 diabetes , and 22 % of coronary heart disease and the burden of these and other chronic diseases has rapidly increased in recent decades .
OBJECTIVES The purpose of this systematic review was to summarize the evidence of the effectiveness of school-based interventions in promoting physical activity and fitness in children and adolescents .