A quarter of young Japanese women are underweight: thin-ideal internalization and self-esteem mediate exercise habits and body satisfaction, but different mechanisms with normal-range weight

The results highlight that the pathways through which exercise habits affect body satisfaction differ according to body mass index. For underweight women, reducing thin-ideal internalization and enhancing self-esteem through exercise habits is crucial. In contrast, interventions directly boosting self-esteem may be more effective for women with normal-range weight. These findings clarify the distinct roles of exercise habits in influencing body satisfaction for underweight and normal-range weight women in Japan.