The purpose of this study is to investigate how the body capital and sexual appeal of female personal trainers interact and influence consumer purchase intention depending on customer gender. To achieve the objectives of this study, a 2 (body capital: moderate muscle vs. developed muscle) × 3 (sexual appeal: non-exposure vs. partial exposure vs. full exposure) × 2 (consumer gender: male vs. female) between-subject experimental design was employed. Additionally, to ensure representativeness of the target population, a random quota sampling method based on gender and stimulus type was used, and 300 of the sampled participants were randomly assigned to each experimental group. The results of the data analysis based on Process Macro Models 4, 7, and 11 revealed that moderate (vs. developed) muscle of female trainers has a relatively more positive impact on consumers’ desire for exercise, indirectly leading to an increase in the intention to register for personal training sessions. The results also showed that such a positive indirect effect of moderate muscle on registration intention was found to be moderated by the sexual appeal of female trainers and consumer gender.