Exploring The Preliminary Effect Of Physical Activity Intervention Through Family And Peer Challenge In Young Adolescents: A Pilot Cluster Randomized Trial

PURPOSE: Social support is a key component influencing physical activity (PA) in young adolescents. Given that parents and peers are major supporters of PA during adolescence, social support from parents or peers can be an effective mediator for increasing adolescents' PA levels. This study examined the preliminary effect of a family and peer challenge intervention using wearable technology on sedentary behavior (SED) and moderate-to-vigorous PA (MVPA) in young adolescents. METHODS: The study design was a three-arm cluster randomized controlled trial to assess a 6-week PA intervention targeted young adolescents. Three classes (51 students; 51% girls, 13.0 ± 0.7 years) within a middle school were randomly selected and then randomly allocated into one of the three groups: (a) Control, (b) Family challenge (FC), or (c) Peer challenge (PC). All participants received a Fitbit activity monitor (Inspire 2) and educational resources about the benefits of PA and self-monitoring skills. Participants in the intervention groups (FC and PC) were additionally given access to a group challenge feature within the Fitbit app that is designed to enable them to share their PA progress and provide encouragement to one another within their group. Primary outcomes were daily SED and MVPA time measured by hip-worn accelerometers. Linear mixed models were used to evaluate the intervention effects on daily SED and MVPA over time, adjusting for covariates. RESULTS: No significant intervention effect on daily SED was observed post-intervention (FC: b = - 20.7 min, 95% CI = - 54.5-14.0; PC: b = - 7.1 min, 95% CI = - 39.4-24.6). Participants in the FC and PC groups engaged in more MVPA by 11.4 min/day (95% CI = - 2.5-25.5) and 1.1 min/day (95% CI = - 12.0-14.2) than those in the control group, respectively; however, these differences were not statistically significant. CONCLUSIONS: Family and peer challenge strategies via the wearable device and its accompanying mobile app did not effectively improve young adolescents' PA. However, the intervention effects are still inconclusive due to the small sample size. Further investigations with appropriate statistical power are needed to determine if these changes lead to the statistical significance that can support intervention effectiveness.