Adolescent Depressive Symptoms, Physical Activity, and Core Self-Evaluation in Chinese Adolescents: Evidence from Mediation and Latent Profile Approaches

Background Adolescent depressive symptoms are a significant mental health concern. Physical activity and core self-evaluation are potential protective factors against mental health issues. However, their combined associations with depression and subgroup heterogeneity in Chinese adolescents remain insufficiently understood. Objective This study examines the relationship between physical activity and core self-evaluation in relation to depressive symptoms, employing both variable-centered and person-centered approaches, and identifies subgroups defined by joint patterns of these variables. Methods Participants included 948 junior high school students (mean age: 12.54 ± 1.11 years; 56.2% female) who completed the Physical Activity Rating Scale, the Core Self-Evaluation Scale, and the depression subscale of the Depression, Anxiety, and Stress Scale‑21. Controlling for sex, grade, and residence, mediation was tested in SPSS using PROCESS Model 4 with 5,000 bootstrap resamples. Item-level indicators were entered into Mplus 8.3 for latent profile analysis (LPA) of physical activity and core self-evaluation. Results Physical activity was inversely associated with depressive symptoms (β = −0.22, p