Background Population aging poses significant challenges to psychological well-being, with depression and social isolation highly prevalent among older adults. Square dance (guangchangwu), a culturally embedded group physical activity widely practiced in China, has been associated with mental health benefits; however, the mechanisms underlying these effects remain insufficiently understood. This study examined whether social participation mediates the relationship between square dance participation and well-being outcomes among older adults. Methods A 12-week, community-based, single-blind randomized controlled trial was conducted with 150 community-dwelling adults aged 60–79 years in Zhengzhou, China. Participants were randomly assigned to a square dance intervention group ( n = 75) or a health education control group ( n = 75). Social participation, subjective well-being (WHO-5), and depressive symptoms (GDS-15) were assessed at baseline and post-intervention. Mediation analyses were performed using PROCESS Model 4 with bootstrapping (5,000 samples), adjusting for demographic and health-related covariates. Results Compared with controls, the square dance group showed significantly greater improvements in social participation (Δ = +3.28), subjective well-being (Δ = +5.73), and reductions in depressive symptoms (Δ = −3.85) (all p 0.001). Mediation analyses demonstrated that social participation significantly mediated the effects of square dance on both well-being (indirect effect = 2.92, 95% CI ≠ 0) and depressive symptoms (indirect effect = −2.82, 95% CI ≠ 0), indicating partial mediation. Discussion Square dance participation significantly enhanced psychological well-being and reduced depressive symptoms among older adults, with social participation statistically accounting for part of the intervention effect. However, because mediator and outcomes were assessed at the same post-intervention time point, causal ordering cannot be definitively established. These findings highlight the importance of culturally meaningful, group-based physical activities as scalable strategies for promoting mental health and social integration in aging populations.
Song et al. (Tue,) studied this question.