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Systematic review of recess interventions to increase physical activity.

BACKGROUND
With the rapid increase in obesity rates among youth, efforts to increase physical activity (PA) have become a priority. School-based strategies for PA promotion must be cost-effective, unobtrusive, and linked to improved academic performance. Efforts to maximize recess PA are advocated because of both health and academic benefits. The purpose of this manuscript was to review recess interventions aimed to improve PA among youth, and make recommendations to develop related best practices.


METHODS
An extensive literature search was conducted to include all primary research articles evaluating any recess intervention with PA as an outcome.


RESULTS
The included 13 interventions represented both settings within the U.S and internationally, among preschools and elementary/primary schools. A variety of strategies were used within the design and implementation of each of the interventions including: added equipment/materials, markings, zones, teacher involvement, active video games, activity of the week, and activity cards. Of the included studies, 95% demonstrated positive outcomes as a result of the recess intervention.


CONCLUSIONS
A number of simple, low-cost strategies can be implemented to maximize the amount of recess time students are allotted. Long-term follow-up studies are warranted for each of the recess strategies identified to be effective.