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 .
Youth: a health plan-based lifestyle intervention increases bone mineral density in adolescent girls.
OBJECTIVE To test the efficacy of a health plan-based lifestyle intervention to increase bone mineral density  in adolescent girls . DESIGN Two-year r and omized , controlled trial . SETTING Large health maintenance organization . PARTICIPANTS Girls 14 to 16 years old with body mass index below the national median .  Intervention Behavioral intervention ( bimonthly group meetings , quarterly coaching telephone calls , and weekly self-monitoring ) design ed to improve diet and increase physical activity . MAIN OUTCOME MEASURES Total bone mineral density was measured by dual-energy x-ray absorptiometry . Behavioral outcomes included intake of calcium , vitamin D , soda , and fruits and vegetables ; high-impact and strength-training physical activity ; measures of strength and fitness ; and biomarkers ( osteocalcin and naltrexone ) . RESULTS Compared with control subjects , girls in the intervention group had significantly higher bone mineral density in the spine and trochanter regions during the first study year , which was maintained during the second study year . The naltrexone biomarker demonstrated a greater relative decrease in the intervention group compared with the control group , with nonsignificant changes in osteocalcin consistent with more bone building in the intervention group . Participants in the intervention group reported significantly greater consumption of calcium in both study years , vitamin D in the first year , and fruits and vegetables in both years . We found no effect on soda consumption or target exercise rates . CONCLUSIONS A comprehensive health care-based lifestyle intervention can effectively improve dietary intake and increase bone mineral gains in adolescent girls . To our knowledge , this study is the first to significantly improve bone mass in adolescent girls in a non-school-based intervention . Trial Registration Clinical Trials.gov Identifier : NCT00067600
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 .