The current study is a randomized controlled trial to test a novel 10-week climate-based intervention within pre-existing afterschool programs, designed to increase moderate-to-vigorous physical activity (MVPA) in underserved (low-income, minority status) middle school youth by addressing youth social developmental needs. Participants (n = 167; 56% female; 62% Black; 50% overweight/obese) enrolled in 6 middle schools were randomized to either the Connect through PLAY intervention or a wait-list control. Process evaluation measures (i.e., observations of external evaluators; staff surveys) indicated that essential elements were implemented with fidelity, and staff endorsed implementation ease/feasibility and acceptability. Regression analysis demonstrated that participation in the intervention (vs. control) was associated with an increase of 8.17 min of daily accelerometry-measured MVPA (56 min of additional weekly MVPA) at post-intervention controlling for baseline MVPA, school, gender, and weight status. The results provide support for social-motivational climate-based interventions for increasing MVPA in underserved youth that can inform future school-based health initiatives.Trial Registration: NCT03850821: https://clinicaltrials.gov/ct2/show/study/NCT03850821?term=NCT03850821&rank=1.
Keywords: Adolescent health; Behavioral change; Health disparities; Implementation science; Moderate-to-vigorous physical activity; Motivational social climate.