IntroductionThe purpose of this study was to explore associations between participation in out-of-school/weekend organized activities and adherence to the 24-hour movement guidelines among US adolescents. MethodsData from the 2022 National Survey of Children's Health (NSCH) (N=16,403, age=15.1±1.4 years, 48.1% female) was used for analyses in 2024. A parent/guardian completed surveys regarding adolescents’ 24-hour movement behaviors (physical activity [PA], sleep [SL], and screentime [ST]), as well as participation in out-of-school and weekend activities (sports, clubs, other organized activities, and volunteering). Weighted logistic regression models were used to examine associations between participation in out-of-school and weekend organized activities and 24-hour movement guideline adherence, adjusted for sex, age, race/ethnicity, federal poverty level status, metropolitan statistical area status, and overweight/obesity status. ResultsOnly 4.8% of adolescents met all three guidelines concurrently. Adolescents who participated in sports teams/lessons had higher odds of meeting PA (OR=2.11,95%CI:1.67-2.66), ST (OR=1.31,95%CI:1.12-1.53), PA+ST (OR=2.24,95%CI:1.63-3.07), PA+SL (OR=2.00,95%CI:1.53-2.63), SL+ST (OR=1.40,95%CI;1.19-1.66), and all three guidelines (OR=2.33,95%CI:1.61-3.39). Participation in other organized activities/lessons was associated with higher odds of meeting ST (OR=1.32,95%CI:1.13-1.56), and SL+ST guidelines (OR=1.39, 95%CI:1.16-1.66). Adolescents who volunteered had higher odds of meeting ST (OR=1.68,95%CI: 1.42-1.98), PA+ST (OR=1.75,95%CI:1.25-2.45), SL+ST (OR=1.64,95%CI:1.38-1.95), and all three guidelines (OR=1.80,95%CI:1.20-2.72). ConclusionsParticipating in sports teams/lessons and community service/volunteer work is beneficially associated with concurrently meeting all three 24-hour movement guidelines and participating in other organized activities or lessons is associated with adherence to individual components of the 24-hour movement guidelines among US adolescents.