Biao Huang, X H Chen, Chang Hu, Wenying Huang, Dong Zhu, Yan Liu, Huiran Feng, Beibei Xu
Background Autistic traits are prevalent among college students and are associated with impaired social functioning and mental health. Although physical activity is considered a protective factor, the underlying mechanisms, particularly the mediating role of social anxiety and the heterogeneity of autistic traits, remain unclear. This study aimed to examine the association between physical activity and autistic traits, test the mediating role of social anxiety, and identify latent subgroups among female college students. Methods A cross-sectional survey was conducted among 2,137 female college students (M_age = 19.31, SD = 1.17). Autistic traits, social anxiety, and physical activity were assessed using the Autism-Spectrum Quotient-10 (AQ-10), the Social Interaction Anxiety Scale-6 (SIAS-6) and the Social Phobia Scale-6 (SPS-6), and the Physical Activity Rating Scale-3 (PARS-3), respectively. Mediation analysis was performed using PROCESS (Model 4), and latent profile analysis (LPA) was conducted to identify subgroups. Results Physical activity was significantly negatively associated with social anxiety ( β = -0.205, p < 0.001) and autistic traits ( β = -0.197, p < 0.001), while social anxiety was positively associated with autistic traits ( β = 0.425, p < 0.001). Social anxiety partially mediated this relationship (indirect effect = -0.087, 95% CI [-0.106, -0.067]), accounting for 31% of the total effect. Latent profile analysis identified two profiles: low autistic traits (74.54%) and high autistic traits (25.46%). The high trait group showed lower physical activity ( t = 7.91, p < 0.001, d = 0.39) and higher social anxiety ( t = -23.25, p < 0.001, d = -1.16). Conclusions Physical activity and social anxiety are key modifiable factors associated with autistic traits. Interventions should promote physical activity while reducing social anxiety, particularly for students with elevated autistic traits.