Physical activity, psychological capital, and mental health equity in children and adolescents: a narrative review and framework development

Background Physical activity is widely promoted for child and adolescent mental health, yet participation and psychological benefit remain unevenly distributed across socioeconomic position, disability, gender, migration status, race and ethnicity, and place. Existing research often examines average effects without distinguishing access from uptake, quality of experience, and equitable benefit. Objective This narrative review synthesises evidence on physical activity, sport, physical education, recess, active play, and active travel in relation to psychological capital and mental health amongst children and adolescents, treating health equity as a structural and distributional concern. The researchers propose the Equity-Scaffolded Psychological Capital Development (ES-PCDF) framework linking equitable access and inclusive, culturally responsive settings to autonomy-supportive pedagogy, supportive relationships, skill transfer, and system continuity, and then to psychological capital and mental health outcomes. Methods A narrative synthesis was conducted using Web of Science exports (502 records) and high-quality Scopus-indexed literature as corroborating evidence. After de-duplication, 238 unique records remained, of which 102 were prioritised for evidence mapping. The final synthesis retained 68 peer-reviewed sources. Results Across the retained evidence, five thematic pathways were identified: equitable access and material opportunity; autonomy-supportive pedagogy and mastery; supportive relationships and social–emotional skill practise; skill transfer and future orientation; and system continuity. These pathways were mapped onto the ES-PCDF framework. Physical activity can improve wellbeing, depressive symptoms, self-esteem, and selected psychological resources, but effects are inconsistent and depend on access, pedagogy, relationships, inclusion, continuity, and context. Benefit equity evidence remains sparse. Conclusion The ES-PCDF framework is presented as a testable public mental health model, not a validated prescription. Statements apply primarily to the school-age and adolescent evidence base, with cautious extension to preschool and older age groups. Policy and practise should combine proportionate universalism with youth co-design, family engagement, inclusion, workforce training, continuity, and disaggregated evaluation of participation, experience, and benefit.