Physical exercise and psychological resilience in the link between adverse childhood experiences and non-suicidal self-injury: chain mediation and network analysis in college students.

BACKGROUND: Non-suicidal self-injury is highly prevalent among college students, and adverse childhood experiences are an important risk factor. Physical exercise and psychological resilience may serve as protective factors in this association, while the item-level structure of NSSI behaviors requires further clarification. METHODS: A cross-sectional design was adopted. A total of 2,626 college students were assessed using the Adverse Childhood Experiences Scale, the Physical Activity Rating Scale (PARS-3), the Psychological Resilience Scale, and the Non-Suicidal Self-Injury Behavior Assessment Questionnaire. Chain mediation analysis was conducted using SPSS 27.0 to examine theory-driven statistical indirect effects, and psychological network analysis was performed using R 4.3.2 to identify relatively central symptom nodes. RESULTS: Adverse childhood experiences were significantly and positively associated with non-suicidal self-injury, and the PROCESS Model 6 analysis indicated a statistically significant indirect association through lower physical exercise and weaker psychological resilience. Further network analysis showed that "deliberately pinching oneself" had the highest expected influence and was involved in the relatively strongest edges in the NSSI symptom network. CONCLUSION: This study supported the statistical indirect roles of physical exercise and psychological resilience in the association between adverse childhood experiences and non-suicidal self-injury, and suggested that "pinching" was a noteworthy symptom in the NSSI behavioral network. The chain mediation and network analyses should be understood as complementary but parallel analyses, providing evidence at the total-score and symptom-item levels, respectively.