The Independent, Joint, and Additive Associations of Physical Activity and Self-Compassion on Depression Symptoms Among Chinese College Students

BACKGROUND: Physical activity and self-compassion are closely related to individuals’ mental health (eg, depression). However, most studies only examined their independent roles in mental health without considering the potential interaction between the two variables. The present study aimed to investigate the independent and joint associations between physical activity (PA) and self-compassion (SC) on depression symptoms and examine the additive interaction between PA and SC. METHODS: A cross-sectional design was utilized in the present descriptive study. By recruiting participants via social media platforms, 1846 Chinese college students completed International Physical Activity Questionnaire Short Form, the Self-Compassion Scale-Short Form, the 9-item Patient Health Questionnaire, and items regarding socio-demographic information. Independent and joint roles of low-level PA (LPA) and low-level SC (LSC) on depression symptoms were examined by logistic regression models. Additive interaction between LPA and LSC on depression symptoms was examined by the following indices: relative excess risk due to interaction (RERI), attributable proportion (AP), and synergy index (S). Socio-demographic variables were included in the models as covariates. RESULTS: Both LPA (OR = 1.47 [1.16, 1.86]) and LSC (OR = 5.74 [3.89, 8.45]) were independently associated with higher probability of depression symptoms. Combining LPA and LSC led to an additive interaction and greatly increased the odds of depression symptoms (OR = 9.62 [5.38, 17.22]; RERI = 2.47 [0.19, 4.75], AP = 0.25 [0.05, 0.44], S = 1.38 [1.02, 1.87]). CONCLUSION: Both LPA and LSC were associated with an increased risk of depression symptoms. Moreover, combining LPA and LSC may develop an additive risk for depression symptoms. Future research and clinical intervention could integrate PA and SC to find a better way to resist depression symptoms.