Afterschool programs can modestly increase the amount of physical activity among girls in middle school, according to new results from the Trial of Activity for Adolescent Girls (TAAG), a multiple site, community based study supported by the National Heart, Lung, and Blood Institute (NHLBI) of the National Institutes of Health.

Results are published in the article, "Promoting Physical Activity in Middle School Girls," in the March issue of the American Journal of Preventive Medicine.

The study found that programs which linked schools in 6 geographic regions of the U.S. with community partners (such as the YMCA or YWCA, local health clubs, and community recreation centers) increased time spent in moderate-to-vigorous physical activity among the middle-school female students by about 2 minutes per day, or 80 calories a week.

This finding occurred after three years of the intervention but not after two years. Physical activity was measured using accelerometers (a device for measuring the acceleration of motion), rather than self-reported. The authors write that results suggest this improved level of activity could prevent excess weight gain of about 2 pounds per year (or 0.82 kg per year), which, if sustained, could prevent a girl from becoming overweight as a teenager or adult.

In addition, TAAG showed a reduction of 8.2 minutes of sedentary behavior in girls in the intervention schools. Furthermore, the best results were seen in programs offered between 2 p.m. and 5 p.m. on weekdays, which suggest that afterschool programs are more effective than programs offered at other times, such as morning weekdays and weekends. The study results support the need for schools and community programs to work together to provide opportunities for physical activity programs in afterschool settings.

Researchers have found that as youth, especially girls, become adolescents, their level of physical activity decreases, putting them at risk for becoming overweight.

Source: National Heart, Lung and Blood Institute