Frequency Domain Analysis of Hamstring Activation During Jump-Landing Performance by Athletes with Diverse Training Regimens

This study investigated hamstring activation in the frequency domain and jump-landing performance in a specialized-training athletic population and a healthy control group. Thirty male athletes engaged in power training, both with and without jumping sports, or endurance training, together with ten healthy participants were recruited. Surface EMG electrodes were attached to the bellies of the lateral hamstring (LH) and medial hamstring (MH). The median EMG frequency was analyzed during takeoff, flight, before ground contact, after ground contact, and landing in countermovement jumps (CMJ) and drop-vertical jumps (DJ). Kinetic outcomes were also investigated. The power-trained athletes (with and without jumping sports) exhibited a lower median EMG frequency in the MH during takeoff (p = 0.001 for DJ) and in the LH (p = 0.008 for DJ) and MH during landing (p = 0.004 for CMJ and 0.001 for DJ) compared with the endurance-trained or control groups. Furthermore, the power-trained group demonstrated greater jump heights (p = 0.009 for CMJ and p = 0.003 for DJ). All the athletic groups showed a lower landing force (p = 0.022) and loading rate (p = 0.043) in CMJ than the control group. Training background differences influenced hamstring recruitment during jumping. Power-trained athletes exhibited a lower median EMG frequency and better jumping performance. All the athletes demonstrated a more effective landing strategy than the control group. These findings suggest the potential for enhancing athletic performance and aiding in landing strategy by exploiting different training styles.