Abstract / Summary
Objectives:: To analyze cardiac autonomic modulation, anxiety symptoms, and physical fitness in male youth soccer players at different stages of sexual maturation. Design:: Cross-sectional study. Methods:: A total of 53 male soccer players were evaluated and classified as prepubescent ( n =22) or pubescent ( n =31) according to Tanner’s self-assessment method. Participants completed the Multidimensional Anxiety Scale for Children (MASC), underwent heart rate variability (HRV) assessment using time, frequency, and nonlinear indices, and performed standardized physical fitness tests following the PROESP-BR protocol. Statistical analyses included Student’s t -test, Mann–Whitney U test, chi-square test, and effect size calculations ( p ≤ 0.05). Results:: Pubescent boys showed higher values of vagal autonomic modulation (RMSSD, HF, SD1) and lower sympathetic dominance (LF/HF ratio) compared to prepubescent boys. Significant differences were also observed in stress levels, with 27.3% of prepubescent participants classified as having elevated stress, versus only 5% among pubescents ( p = 0.009). Physical fitness outcomes indicated superior aerobic capacity, lower limb power, and agility in pubescent players (all p < 0.05). Anxiety scores tended to be higher in prepubescents, although the difference did not reach statistical significance ( p = 0.06). Conclusions: Sexual maturation is associated with improved cardiac autonomic function, reduced stress, and enhanced physical fitness in youth soccer players. Pubertal status should be considered when evaluating physiological and psychological adaptations in young athletes.