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

While elite soccer cultivates concurrent cardiovascular and neuromuscular adaptations, the functional interplay between exercise-induced left ventricular hypertrophy (LVH) and explosive power remains underexplored.

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).

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/m²).

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 (BF₁₀ = 3.47). Other RVJT parameters were unaffected.

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.