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Trial of Activity for Adolescent Girls (TAAG)

The Trial of Activity for Adolescent Girls (TAAG) tested interventions to reduce the usual decline in moderate-to-vigorous physical activity in middle school girls. TAAG was a multi-center, group-randomized trial in which schools were randomly assigned to intervention or comparison condition over two years. Random cross-sectional samples of girls were taken at 6th grade (1,721 girls) in the spring of 2003 prior to the interventions, 8th grade (3,504 girls) in the spring of 2005 at end of study-delivered interventions, and 2006 (3502 girls) one year after school- and community personnel-delivered interventions ceased. Thirty-six schools and many community partners participated to provide skills-building, supportive environments, and opportunities for participation in physical activity during and outside of the school day.

TAAG demonstrated that afterschool programs can modestly increase the amount of physical activity among girls in middle schools. Programs 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. These 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.

Selected References:

Webber LS, Catellier DJ, Lytle LA, et al. Promoting physical activity in middle school girls: Trial of Activity for Adolescent Girls. Am J Prev Med 2008;34:173-84.

Study Website:

TAAG Study Websiteexternal disclaimer

Press Release:

After School Programs Can Increase Physical Activity of Adolescent Girls

Last Updated May 2011

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