The Secret Sauce? Taking the Mystery Out of Scaling-Up School-Based Physical Activity Interventions.

Over the last 4 decades, physical activity researchers have invested heavily in determining "what works" to promote healthy behaviors in schools. Single and multicomponent school-based interventions that target physical education, active transportation, and/or classroom activity breaks effectively increased physical activity among children and youth. Yet, few of these interventions are ever scaled-up and implemented under real-world conditions and in diverse populations. To achieve population-level health benefits, there is a need to design school-based health-promoting interventions for scalability and to consider key aspects of the scale-up process. In this opinion piece, we aim to identify challenges and advance knowledge and action toward scaling-up school-based physical activity interventions. We highlight the key roles of planning for scale-up at the outset, scale-up pathways, trust among partners and program support, program adaptation, evaluation of scale-up, and barriers and facilitators to scaling-up. We draw upon our experience scaling-up effective school-based interventions and provide a solid foundation from which others can work toward bridging the implementation-to-scale-up gap.