<b>Body Composition, Somatotype, and Phantom Strategy (Z-Score) in Elite Combat Sports Athletes: A Comparative and Correlational Study</b>

Background: Body composition (BC) and anthropometric characteristics are critical for optimizing performance in combat sports, yet comparative analyses across Jiu-Jitsu, Muay Thai, Wrestling, and Taekwondo remain limited. This study aimed to analyze BC, anthropometric measures, and Phantom z-score in elite male athletes to identify sport-specific differences and their relationship with performance. Methods: Sixty-eight elite male athletes (Jiu-Jitsu: n=19; Muay Thai: n=15; Wrestling: n=19; Taekwondo: n=17) from Brazil and Colombia were assessed using International Society for the Advancement of Kinanthropometry (ISAK) protocols. Anthropometric measurements (skinfolds, circumferences, bone diameters) were used to evaluate BC and somatotype via the Heath-Carter method, with z-scores calculated using the Phantom strategy. Statistical analyses included ANOVA, Tukey post hoc tests, and Pearson correlations (p<0.05). Results: Significant differences were found in arm circumferences, waist circumference, and femur breadth, particularly between Jiu-Jitsu and Taekwondo, and Wrestling and Taekwondo (p<0.001, η²=0.20–0.49). Jiu-Jitsu, Muay Thai, and Wrestling athletes exhibited endo-mesomorphic somatotypes, while Taekwondo athletes were ecto-mesomorphic. The Petroski equation showed the strongest correlations with anthropometric variables (r=0.32–0.94, p<0.01), while the Withers equation demonstrated the fewest differences compared to other equations, indicating stability. Conclusions: Sport-specific BC profiles highlight distinct morphological adaptations in combat sports. The Petroski equation is a robust tool for BC assessment, with potential for optimizing performance and athlete selection. These findings underscore the need for tailored BC monitoring in competitive contexts involving weight categories.