Physical activity domains and suicidal ideation: Findings from a nationally representative Korean survey

• Domain-specific physical activity showed heterogeneous associations with suicidal ideation. • High work-related physical activity was associated with higher suicidal ideation in men. • The association with work-related activity was strongest among younger men. • Leisure-time physical activity was inversely associated with suicidal ideation in older men. • Associations varied by occupational group, highlighting contextual differences in activity. Suicide is a major public health issue, and Korea has the highest suicide rate among OECD countries. Suicidal ideation is a precursor to suicide. Although physical activity benefits mental health, evidence for its link with suicidality is inconsistent, particularly regarding domain-specific effects. We examined domain-specific physical activity in relation to suicidal ideation in a nationally representative sample of Korean adults. We analyzed data from 31,723 adults aged ≥19 years in the Korea National Health and Nutrition Examination Survey (2015–2023). Suicidal ideation was self-reported, and physical activity was measured with the WHO Global Physical Activity Questionnaire. The Metabolic equivalent (MET)-minutes/week for work, leisure, and transportation time were calculated separately. Multiple logistic regression with survey weights was used, with subgroup analyses by sex, age, and occupation. Exploratory mediation analysis was conducted to examine depression as a mediator in association between domain-specific physical activity and suicidal ideation. 4.8% of participants reported suicidal ideation. In men, high work activity remained significantly increased odds for suicide ideation, particularly among those aged 19–39 years (OR=2.21, 95% CI: 1.17–4.15) and in pink-collar workers (service and sales workers) (OR=3.36, 95% CI: 1.45–9.09), while high leisure activity was protective in those ≥60 years (OR=0.18, 95% CI: 0.07–0.48). No significant associations between physical activity and suicidal ideation were observed in women. Domain-specific physical activity was differentially associated with suicidal ideation. Work-related activity increased risk in certain male subgroups, whereas leisure-time activity was protective in older men, underscoring the need to consider activity context in suicide prevention.