Chasse-Step and One-Step Footwork Reported Different Biomechanical Profiles in Elite Table Tennis Athletes.

Table tennis athletes are required to execute appropriate footwork moving to the best position to hit the ball, while the chasse-step and one-step are typically employed in table tennis. This study aims to examine the difference in joint angles, joint moments, joint contact forces, and activation of lower limb muscles during the stance of chasse-step and one-step. Eighteen male table tennis athletes volunteered to perform topspin forehand with chasse-step and one-step. An eight-camera motion capture system and instrumented force plate were used to record makers' trajectories and ground reaction force, which was then used to calculate the kinematics and kinetics with Inverse Kinematics and Inverse Dynamics in OpenSim. Surface electromyography signals were measured to validate the musculoskeletal OpenSim modeling. Hip flexion angle and moment increased in the backward swing phase during the stance of one-step. Knee extension of the chasse-step increased more during the forward swing phase. Hip contact force increased in the anterior-posterior direction of one-step and the chasse-step in the medial-lateral direction. Key findings suggest that the chasse-step may increase the quality of footwork performance and prepare the next step but shows higher injury risk in knee joints. While the one-step may have faster performance for scoring and high injury risk in hip joint. The information may provide implications for athletes and coaches to improve athletic performance and develop specific footwork training schemes to prevent potential injuries.