Impact of an after-school physical activity program on obesity in children

To assess the impact of a 2-year recreational physical activity program in 1044 fourth- and fifth-grade primary schoolchildren from the Province of Cuenca, Spain.

Cluster-randomized controlled trial with 10 intervention and 10 control schools. The program consisted of 3 90-minute sessions of physical activity per week,during 28 weeks every year.Changes in endpoints between baseline (September 2004) and the end of follow-up (June 2006) were compared between the control and intervention group by using mixed regression models, with adjustment for the baseline endpoint value, age, and the school.

Compared with control subjects, intervention girls reduced the frequency of overweight (odds ratio, 0.55; 95% CI, 0.39-0.78; P<.001). However, intervention was associated with an increase in the percentage of body fat in boys (0.97%; 95% CI, 0.14-1.81; P=.02). Girls in the intervention group had lower total cholesterol level (-6.86 mg/dL; 95% CI, -9.70--4.01; P<.001) and apolipoprotein B level (-3.61 mg/dL; 95% CI, -6.27--0.95; P=.008) than control subjects. Results were similar in boys.

In 2 years, the physical activity program lowered the frequency of overweight in girls and reduced total cholesterol and apolipoprotein B in both girls and boys.