Physiological Profile, Mediterranean Diet Adherence and Supplement Use in Recreational Adults Engaged in Contemporary Gym-Based Exercise Modalities

Physical exercise is a major determinant of health and functional capacity, yet direct comparisons among contemporary gym-based exercise modalities remain limited. This cross-sectional study compared the fitness, dietary, and supplement-use profile of 148 healthy recreational adults (72 men and 76 women; aged 18–45 years) engaged in mixed aerobic-resistance training (n = 52), Pilates (n = 46), or CrossFit (n = 50). Participants underwent cardiopulmonary exercise testing to determine the maximal oxygen uptake (VO2max) and ventilatory anaerobic threshold (VAT). Body composition, handgrip strength, flexibility, Mediterranean diet adherence, and supplement use were also assessed. Participants in CrossFit and mixed training showed higher VO2max and lower fat mass than the Pilates participants. Pilates showed higher VAT expressed as a percentage of VO2max; however, this finding should be interpreted as a relative submaximal profile rather than evidence of superior overall aerobic fitness. Mixed training and CrossFit also showed more favorable body composition profiles, while mixed training demonstrated superior handgrip strength. Flexibility did not differ significantly among exercise modalities. Mediterranean diet adherence showed limited and sex-specific differences, which were attenuated after adjustment for age and training age. Overall, exercise modality was associated with distinct physiological and nutritional characteristics, with CrossFit and mixed training showing greater cardiorespiratory fitness and more favorable body composition characteristics, whereas Pilates was linked to a different submaximal exercise profile and specific lifestyle-related patterns. These findings should be interpreted with caution given the cross-sectional design and the possibility of self-selection bias.