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 .
Improvement of fitness, body composition, and insulin sensitivity in overweight children in a school-based exercise program: a randomized, controlled study.
BACKGROUND Obesity and poor physical fitness constitute a health problem affecting an increasing number of children . Causes include a pervasive " toxic " environment that facilitates increased caloric intake and reduced physical activity . An effective strategy for prevention and treatment of childhood obesity likely includes a collaborative effort in the school setting . OBJECTIVE To determine whether a school-based fitness program can improve body composition , cardiovascular fitness level , and insulin sensitivity in overweight children . DESIGN Fifty overweight middle school children with a body mass index ( BMI ) above the 95th percentile for age were r and omized to lifestyle-focused , fitness-oriented gym classes ( treatment group ) or st and ard gym classes ( control group ) for 9 months . Children underwent evaluation of  fasting insulin and glucose levels , body composition by means of  dual energy absorptiometry , and maximum oxygen consumption ( V0(2)max ) treadmill testing  at baseline ( before the school year ) and at end of the school year . SETTING S Rural middle school and an academic children 's hospital . MAIN OUTCOME MEASURES Baseline test results for cardiovascular fitness , body composition , and fasting insulin and glucose levels . RESULTS At baseline , there were no differences between groups before intervention ( values for age , 12 + /- 0.5 years [ all results , mean + /- SD ] ; BMI [ calculated as weight in kilograms divided by the square of height in meters ] , 31.0 + /- 3.7 ; percentage of body fat , 36.5 % + /- 4.6 % ; lean body mass , 41.4 + /- 8.6 kg ; and V0(2)max , 31.5 + /- 5.1 mL/kg per minute ) . Compared with the control group , the treatment group demonstrated a significantly greater loss of body fat ( loss , -4.1 % + /- 3.4 % vs -1.9 % + /- 2.3 % ; P = .04 ) , greater increase in cardiovascular fitness ( V0(2)max , 2.7 + /- 2.6 vs 0.4 + /- 3.3 mL/kg per minute ; P<.001 ) , and greater improvement in fasting insulin level ( insulin level , -5.1 + /- 5.2 vs 3.0 + /- 14.3 microIU/mL [ -35.4 + /- 36.1 vs 20.8 + /- 99.3 pmol/L ] ; P = .02 ) . CONCLUSIONS Children enrolled in fitness-oriented gym classes showed greater loss of body fat , increase in cardiovascular fitness , and improvement in fasting insulin levels than control subjects . The modification to the school physical education curriculum demonstrates that small but consistent changes in the amount of physical activity has beneficial effects on body composition , fitness , and insulin levels in children . Partnering with school districts should be a part of a public health approach to improving the health of overweight children
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 .