Load-Dependent Modulation of Intermuscular Coherence During Drop Jumps in Female Athletes: Insights Into the...

Uslu, S and Cetin Ozdogan, E. Load-dependent modulation of intermuscular coherence during drop jumps in female athletes: Insights into the performance optimization. J Strength Cond Res XX(X): 000-000, 2026-Mechanical outcomes of drop jumps (DJs) are well-documented; however, how mechanical load modulates neuromuscular coordination in female athletes remains unclear -an issue of particular importance for performance and injury. Despite widespread use of DJs in training and assessment, the neural mechanisms and injury risk remain underexplored. Intermuscular coherence (IMC) provides frequency-specific insights into shared synaptic input and corticospinal drive, which may refine training programs and injury prevention. Thirty-six physically active female athletes performed DJs from 30, 40, 50, and 60 cm. Surface electromyography from tibialis anterior and medial gastrocnemius (dominant leg) was processed, and IMC was quantified within delta, alpha, beta, and gamma bands during pre- and postcontact phases. Ground contact time (GCT), jump height, and reactive strength index (RSI) were measured. Repeated-measures analyses of variance with Bonferroni adjustments tested the effect of height. The statistical significance level was set at p < 0.05 for all analyses. Drop jump height significantly affected performance: GCT, F (2.08-72.67) = 12.41, p < 0.001; RSI, F (2.43-85.07) = 27.45, p < 0.001; jump performance, F (1.96-68.57) = 8.81, p < 0.001. Intermuscular coherence was also height-dependent. Delta-band coherence declined with increasing height (precontact: F (3-105) = 8.61, p < 0.001; postcontact: F (1.93-67.63) = 30.88, p < 0.001). Beta-band coherence showed the strongest suppression at 30 cm, while 40-50 cm showed higher values. Moderate heights (≈40-50 cm) optimize neuromechanical efficiency and performance while maintaining beta/gamma coherence, whereas 60 cm prolongs GCT, decreases RSI, and suppresses beta-band IMC, representing neuromechanical overload. Concurrent assessment of IMC and RSI might provide criteria for individualized DJ applications and for early identification of neuromuscular deficits relevant to injury prevention.