Is the association of physical activity with mental burden mediated by quality of life? A cross-sectional study with undergraduate students

Background The literature lacks studies investigating the role of quality of life in the relationship between physical activity and mental health. The objectives were: i) to analyze the association of physical activity with mental burden among college students and ii) to determine whether the domains of quality of life mediate the association between physical activity and mental burden. Methods A cross-sectional study with a random sample of undergraduate students from southern Brazil was conducted. The data collection was carried out in 2019 using self-administered questionnaires. Depression, anxiety, and stress outcomes were clustered, resulting in three clusters (very high, high, and low risk of mental burden). A general structural equation model was used to examine mediation. Results This study analyzed data from 766 individuals (66% of the eligible sample). The prevalence of active individuals (150 min/wk or more) was 2.5-fold greater for cluster 3 of mental burden (lower risk) compared to cluster 1 (higher risk). The physical and psychological domains of quality of life mediated the association between physical activity and mental burden. Conclusion Physical activity had a protective effect on mental burden, partially mediated by physical and psychological domains of quality of life.