Intervention to increase physical activity and healthy eating among under-represented adolescents: GOAL trial protocol.

introductionTo reduce obesity-related disparities, reaching economically disadvantaged and/or minority status adolescents to assist them in meeting physical activity (PA) and nutrition recommendations is important. To address the problem, a 16-week intervention called Guys/Girls Opt for Activities for Life (GOAL) was designed. The purpose of this randomised controlled trial is to evaluate any effect of the intervention, compared with a control condition, on improving: (1) adolescents' % body fat (primary outcome), moderate-to-vigorous PA (MVPA), diet quality and cardiorespiratory fitness from 0 to 4 months; (2) body mass index (BMI), overweight/obesity percentage and quality of life from 0 to 4 months and to 13 months; and (3) perceived social support, self-efficacy and motivation from 0 to 4 months with evaluation of any mediating effect on adolescent PA and diet quality. An exploratory aim is to evaluate any effect of the intervention, compared with the control, on improving parents'/guardians' home environment, MVPA and diet quality from 0 to 4 months; and BMI from 0 to 4 months and to 13 months. METHODS AND ANALYSIS: Adolescents (fifth to eighth grade) in 14 schools located in underserved urban communities are randomly assigned to the intervention or usual school offerings. One parent per adolescent is enrolled (882 dyads total). Cohort 1 includes four schools (2022-2023). Cohorts 2 and 3 include 5 schools in 2023-2024 and 2024-2025, respectively. The 16-week intervention has three components: (1) after-school GOAL club for adolescents to engage in PA and healthy eating/cooking activities; (2) three parent-adolescent meetings to empower parents to assist adolescents; and (3) GOAL social networking website for parents to share how they helped their adolescent. ETHICS AND DISSEMINATION: The Michigan State University Biomedical Institutional Review Board provided ethical approval for the study. Findings will be shared via the trial registration database, peer-reviewed publications, conferences and community-oriented strategies. TRIAL REGISTRATION NUMBER: NCT04213014.