Weight Self-Stigma and Home Physical Activity in Adolescents: A Moderated Mediation Model

Background: Physical activity deficiency among adolescents represents a significant public health concern, particularly in home settings. While weight self-stigma has been identified as a potential barrier to physical activity, the mechanisms underlying this relationship remain unclear. Objective: This study examined how weight self-stigma influences adolescents’ home physical activity through psychological needs satisfaction in exercise and investigated the moderating role of family physical activity climate in this relationship. Method: Participants were 1,328 adolescents (676 males, 656 females) from three cities in Hunan Province, China. Data were collected at two time points to minimize common method bias. Participants completed measures of weight self-stigma, psychological needs satisfaction in exercise, family physical activity climate, and home physical activity. Results: Weight self-stigma negatively affected home physical activity (β = −0.488, p < 0.01). Psychological needs satisfaction in exercise partially mediated this relationship, with a significant indirect effect (β = −0.159, 95% CI [−0.200, −0.124]). Family physical activity climate moderated the relationship between psychological needs satisfaction and home physical activity (β = 0.216, p < 0.01). The moderated mediation analysis revealed stronger indirect effects at high levels of family physical activity climate (β = −0.226, p < 0.01) compared to low levels (β = −0.011, ns). Conclusion: These findings suggest that weight self-stigma impairs adolescents’ home physical activity both directly and indirectly through reduced psychological needs satisfaction, while a positive family physical activity climate can buffer these negative effects.