Depressive symptoms as a mediator in the association between regular physical activity and irritable bowel syndrome-related symptom severity: a cross-sectional study among college students.

Introduction: Irritable bowel syndrome (IBS) is a common functional gastrointestinal disorder, substantially affecting quality of life among young adults. Although regular physical activity (RPA) benefits both mental and gastrointestinal health, its potential psychological mechanisms in IBS-related symptom severity remain unclear. This study was designed to examine the association between RPA and IBS-related symptom severity among Chinese college students and to clarify the mediating roles of depressive symptoms. Methods: A cross-sectional survey was conducted among 872 students from three universities in Shandong Province, China. Data on demographics, RPA, anxiety and depression assessed by the Self-Rating Anxiety Scale (SAS) and Self-Rating Depression Scale (SDS), and IBS-related symptom severity evaluated using the Irritable Bowel Syndrome Severity Scoring System (IBS-SSS) and the Gastrointestinal Symptom Rating Scale (GSRS) were collected. Group comparisons, multiple regression, and mediation analyses were performed. Results: Comparisons between students engaging in RPA and their sedentary peers revealed significantly lower IBS-SSS and GSRS scores in the RPA group. Consistent with these observations, multiple linear regression indicated that RPA was inversely associated with IBS-SSS [ Conclusion: These findings indicate that RPA is associated with reduced IBS-related symptom severity, and that depressive symptoms statistically account for part of this association, highlighting the importance of lifestyle strategies integrating physical and psychological interventions for managing IBS-related symptom in young adults.