Sex differences in coordination of center of mass kinematics during table tennis footwork.

Table tennis requires dynamic stability during the execution of fast movements, and the Center of Mass (COM) is a key parameter describing balance control. This study aimed to analyze the COM differences between males and females during chasse-step footwork using vector coding to understand the sex-specific coordination patterns. Eighteen male and eighteen female national-level athletes participated in the motion capture analysis, with data collection using an 8-camera Vicon motion capture system with 52 markers attached and a force platform. The segmental COM velocity (sCOM) and body COM (bCOM) position were analyzed with inverse kinematics using OpenSim (v4.2). During the forward swing, the sCOM velocity mappings of the lower extremity, including pelvis-torso, pelvis-femur, and femur-tibia, were all in-phase with proximal dominance, while females were anti-phase with distal dominance. Significantly higher coordination variability was observed in the pelvis-torso (p < 0.001) and pelvis-femur (p = 0.002) in males. In the following phase, the coordination in the upper limb, including the torso-humerus and humerus-forearm, showed distal dominance in males and proximal dominance in females, but females showed higher variability (p = 0.005). Furthermore, at the end of the following stage, the segmental velocity pattern of both males and females was in the forearm dominance. During the entire movement, the sCOM of the whole body was faster than that of females (p < 0.05), and the bCOM position of males was lower (p = 0.047). Exploring the inter-segment coordination of sex-specific movements may provide an in-depth understanding of the movement patterns in male and female table tennis athletes. The profiles of sCOM velocity coordination may practically imply the development of sex-specific training programs for males and females to control dynamic balance.