The benefits of physical activity are numerous and well-documented. Children who are physically active have a lower risk of obesity and diabetes, perform better on academic tasks, and exhibit more desirable classroom behaviors. Despite the importance of physical activity, few children in the U.S. meet the current daily recommendation of at least 60 minutes of moderate-to-vigorous physical activity (MVPA). Further, low levels of physical activity may be concentrated in certain demographic subgroups. Studies have consistently documented persistent gender differences in children’s physical activity, with boys exhibiting higher levels of MVPA than girls, both overall and during school recess periods. The evidence for racial and ethnic disparities is plentiful but mixed, with some studies suggesting that physical activity levels may be lower for racial and ethnic minorities. Schools, and recess in particular, present a potential solution to increasing children’s physical activity. Some evidence suggests that school-based programs can successfully target vulnerable subgroups. Playworks is a school-based program that places full-time coaches in low-income, urban schools to organize games and other activities during recess in an effort to increase children’s physical activity. However, no rigorous studies of the Playworks program have been conducted previously.

This study seeks to fill that gap. We use a rigorous design to assess the impact of Playworks on the physical activity of students, by race/ethnicity, during recess. The study collected data from a large sample of students from 29 urban elementary schools across the country, 17 of which were randomly assigned to implement the Playworks program and 12 of which were randomly assigned to a control group that were asked to delay implementation of Playworks for a year. Our analysis sample includes 968 fourth and fifth graders who wore accelerometers during recess. Three hundred and thirty five of those students were black (35%), 412 were Hispanic (43%), and 221 were white (23%). We examined the impacts of Playworks separately for these three groups. We focused on three outcomes based on the accelerometer data: (1) the mean number of accelerometer intensity counts recorded per minute during recess, (2) the mean number of steps taken per minute during recess, and (3) time spent in MVPA during recess.

We found statistically significant, positive impacts of Playworks on all three outcomes for black students. There were no statistically significant impacts for the other race/ethnicity groups. Another study which used the same data also found that Playworks had an impact on girls, but not boys. These findings suggest that Playworks may work better at increasing physical activity for demographic subgroups that often have lower levels of physical activity, such as girls and racial and ethnic minorities.