Self-compassion buffers associations between body-related threats and appearance-motivated physical activity...

Young adult women are frequently exposed to body-related threats, such as appearance-related social comparisons, which are theorized to promote appearance-driven motives for physical activity and undermine more adaptive forms of engagement. Self-compassion may function as a protective resource that buffers the motivational consequences of these threats and supports more health-oriented motives for physical activity engagement. However, the impact of momentary fluctuations in body-related threats and self-compassion on physical activity motives in daily life remains underexplored. The present study examined within- and between-person associations among body-related threats, self-compassion, and physical activity motives in the daily lives of young adult women. A sample of 148 women completed a 7-day mobile ecological momentary assessment (M_age = 20.63 years, SD_age = 2.10). Within individuals, momentary body-related threats were associated with stronger endorsement of appearance-motivated physical activity behaviour. Momentary self-compassion moderated the association between body-related threats and appearance motives, such that higher-than-usual self-compassion attenuated the link between threats and appearance-motivated physical activity behaviour. Between individuals, women with higher average self-compassion reported stronger health motives when body-related threats were more frequent, whereas women with lower average self-compassion reported weaker health motives under similar threat frequency. Together, these findings suggest that body-related threats primarily shape women's physical activity motives in the moment and that self-compassion functions as a transient protective resource by buffering appearance-driven motivational responses to threat and also supporting health-focused motivation under more frequent threat exposure.