Stronger hearts, weaker leaps? The cardiac power paradox in elite soccer

Abstract While elite soccer cultivates concurrent cardiovascular and neuromuscular adaptations, the functional interplay between exercise-induced left ventricular hypertrophy (LVH) and explosive power remains underexplored. Purpose The purpose of the study was to determine if left ventricular mass index (LVMI), a primary marker of cardiac adaptation, is associated with explosive power assessed via a repetitive vertical jump test (RVJT). Methods Nineteen elite male soccer players underwent 2D echocardiography for LVMI and a 15-repetition RVJT on a force plate for maximum jump height (h MAX ). The relationship was tested using hierarchical regression (controlling for body mass and experience), Bayesian analysis, and group comparisons based on the clinical LVH threshold (≥ 115 g/m 2 ). Results An inverse LVMI–h MAX relationship was observed ( r = − 0.53, p = 0.02). In the adjusted model, LVMI showed B = − 0.00123 m per g·m⁻ 2 (SE 0.00046; 95% CI [− 0.00220 to − 0.00026]; standardized β = − 0.63; p = 0.02); after Benjamini–Hochberg correction across five RVJT outcomes, q = 0.10. Athletes with high LVMI exhibited 17% lower h MAX than their normal-LVMI counterparts (0.29 ± 0.04 vs. 0.35 ± 0.04 m; p = 0.003, Hedges’ g = − 1.51), with moderate Bayesian support ( BF 10 = 3.47). Other RVJT parameters were unaffected. Conclusion The findings are preliminary and hypothesis generating, consistent with a potential trade-off between cardiac remodeling and maximal explosive performance in elite male soccer. Greater cardiac mass is associated with attenuated explosive power capacity, a functional “cardio-neuromuscular paradox.” The RVJT may serve as a practical tool to monitor this systemic balance and inform training adjustments to preserve power in athletes with pronounced cardiac remodeling.