Association between work-related physical activity and depressive symptoms in Korean workers: data from the Korea national health and nutrition examination survey 2014, 2016, 2018, and 2020

Background The workplace experiences of employees can impact their mental health. Depressive symptoms, which are experienced by workers, are a mental health issue that deserves attention. Several studies have evaluated physical activity to prevent possible depression in workers in a work environment, however, research on physical activity and depression symptoms directly related to work is still insufficient. Therefore, we aimed to identify the relationship between work-related physical activity and depression among South Korean workers.Methods We used data from the Korean National Health and Nutrition Examination Survey conducted in 2014, 2016, 2018, and 2020, which included 31,051 participants. We excluded, participants aged < 15 years (n = 4,663), unemployed and economically inactive persons (n = 9,793), those who did not engage in work-related physical activities (n = 1,513) and leisure physical activities (n = 1,558), or those with missing data (n = 450). Therefore, the study included 13,074 participants. Work-related activity was measured by self-reporting, while depressive symptoms were measured using the Patient Health Questionnaire-9 (PHQ-9). Multiple logistic regression analysis was performed to investigate the association between work-related physical symptoms and depressive symptoms among workers.Results Individuals who engaged in work-related physical activity had higher PHQ-9 scores than those who did not (male: odds ratio [OR]: 1.71, 95% confidence interval [CI]: 1.16-2.52; female: OR: 2.33, 95% CI: 1.66-3.29). High-intensity work-related physical activity significantly increased depressive symptoms (male: OR: 2.15, 95% CI: 1.04-4.43; female: OR: 2.90, 95% CI: 1.46-5.96). When classified according to the severity of depressive symptom, the OR of depressive symptoms of workers engaged in both leisure and work-related physical activities tended to be lower than that of those engaged only in work-related physical activities.Conclusion Korean workers who engaged in work-related physical activities exhibited more depressive symptoms. Therefore, our findings suggest that balancing work-related and leisure physical activities can help Korean workers prevent development of depressive symptoms.