Athletes’ bodies are both performance agents and targets of evaluative scrutiny, yet little is known about the psychological processes linking body composition to body image among athletes. In this pre-registered study, we examined whether competence-related self-evaluations mediate or moderate associations between adiposity and body image in 327 Chinese collegiate athletes (78.6% male). Drawing on Self-Objectification Theory and the Sport Confidence Model, we tested two competing hypotheses, including a filter (parallel mediation) and a buffer (moderation) account. Factor analysis results of four body image scales supported a two-factor structure, comprising a proactive, functionality-oriented positive dimension and a reactive, appearance-distress-driven negative dimension.

Hierarchical regressions showed that fat mass index (FMI) was associated with lower positive and higher negative body image (ps < 0.05). Importantly, parallel mediation analysis results indicated that trait sport confidence mediated between FMI and both body image dimensions, with a stronger effect for positive body image (β = −0.04, 95% CI [−0.09, −0.01]) than for negative body image (β = 0.03, 95% CI [0.01, 0.07]). Subjective sport performance was not evidenced as a mediator. No moderation effects were supported. These findings suggest that the body composition–body image link in athletes is interpretive: enduring competence beliefs may matter more than proximal performance appraisals in affecting how athletes make sense of their bodies. Positive body image appears especially dependent on competence-grounded meaning-making, whereas negative body image remains more directly tied to appearance-based evaluative cues. Collegiate sport environments may benefit from prioritizing functionality-centered feedback over physique-focused evaluation.

The authors have declared no competing interest.

This study did not receive any funding

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Ethical approval was obtained from the Ethics Committee of South China Normal University (Approval #: SCNU-SPT-2023-008).

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