The relationship between perceived peer motivational climate and moderate-to-vigorous physical activity in middle school physical education classes using triaxial accelerometers: an analysis of a dual-process model.

Background: Adolescents' moderate-to-vigorous physical activity (MVPA) levels are declining, and peer climate and motivational factors in physical education (PE) classes are closely associated with MVPA, but the interaction mechanisms among them remain to be further clarified. This study aimed to examine the relationship between perceived peer motivational climate and MVPA during PE classes and to test the dual-path mediating roles of autonomous and controlled motivation. Methods: Participants included 596 students (313 boys and 283 girls in grades 7-9) from five middle schools in Daegu, South Korea. MVPA levels were measured using triaxial accelerometers, while peer motivational climate and student motivation were assessed via questionnaires. Results: First, peer motivational climate, motivation, and MVPA levels differed significantly by gender and grade, with girls and higher-grade students scoring lower in task-involving climate, autonomous motivation, and MVPA. Second, a task-involving climate significantly predicted MVPA, and both autonomous motivation and controlled motivation served as mediators in this relationship. In contrast, an ego-involving climate significantly predicted MVPA, in which only controlled motivation played a mediating role, while autonomous motivation did not show a significant mediating effect. Overall, the negative effect of ego-involving climate was stronger than the positive effect of task-involving climate. Conclusion: It may be beneficial in physical education to consider girls and higher-grade students, while reducing exposure to ego-involving climates and fostering task-involving climates, which may be associated with higher levels of MVPA.