Abstract / Summary
Adolescence is critical for developing physical activity habits and maintaining mental health. Using data from the 21st Korea Youth Risk Behavior Survey (2025), this cross-sectional study examined the associations between physical activity and mental health in Korean adolescents. The sample included 52,618 middle and high school students. Physical activity included ≥60 min/day of physical activity, vigorous physical activity, muscle-strengthening exercise, active transportation, and physical education class participation. Mental health indicators included stress perception, depressive symptoms, suicidal ideation, suicide plans, and suicide attempts; stress perception was examined descriptively, whereas depressive symptoms and suicide-related indicators were evaluated as outcomes in the multivariable analyses. Analyses accounted for the complex survey design, including sampling weights, stratification, and clustering. Survey-adjusted tests and complex-sample multivariable logistic regression were performed, adjusting for sex, grade, academic achievement, household economic status, living arrangement, and weight status. Vigorous physical activity and physical education participation were significantly associated with all four mental health outcomes. Compared with no vigorous physical activity, participation on 1–2 days was associated with lower odds of suicidal ideation (aOR = 0.875, 95% CI: 0.811–0.944), suicide plans (aOR = 0.810, 95% CI: 0.720–0.912), and suicide attempts (aOR = 0.803, 95% CI: 0.688–0.937). Physical education twice per week was associated with lower odds of all four outcomes (aORs = 0.737–0.927). In contrast, several frequency categories of ≥60 min/day of physical activity and muscle-strengthening exercise were associated with higher odds of depressive symptoms. These findings suggest that associations between physical activity and mental health vary by activity type and mental health outcomes.