Background: Although the increases in overweight and obesity observed for several decades have appeared to have leveled off, the prevalence of overweight and obesity remains exceptionally high among children of color. This article estimates the effect of Healthy Harlem's Get Fit-a 12-week after-school program aimed at helping students improve physical activity and eating habits-on BMI and weight status of adolescents. Methods: Participants were 436 students who had overweight or obesity in 12 Harlem Children's Zone after-school programs in New York. The evaluation was a randomized controlled trial where students were assigned to an intervention group that received Get Fit plus Prevention services or a control group that only received Prevention services in 2013 or 2014. Impacts were assessed on BMI z-score, percentage with overweight or obesity, and percentage with obesity using regression analysis. Results: Relative to the control group, students randomized to Get Fit experienced a decrease in BMI z-score (mean difference = -0.04; p = 0.02). The percentage of students with overweight or obesity was also lower (mean difference = -5.3; p = 0.02), but there was no effect on the percentage of students with obesity. Get Fit had an impact on BMI for girls, but not boys. Conclusions: Get Fit improved middle- and high-school students' BMI outcomes and weight status. Schools continue to face pressure to allocate time for physical education and activity while meeting their academic demands, underscoring the importance of after-school student-level interventions like Get Fit.
Keywords: high school; middle school; obese; overweight; randomized controlled trial.