Kinematics of Topspin Stroke Combinations in Table Tennis and its Inter-Individual Variability.

This study aimed to (1) determine the kinematics of the different body parts during the execution of one of the basic combinations of plays - a few selected strokes and the footwork used to combine them, and (2) evaluate the variation of these kinematics. The study included eight male advanced-level (polish national team) table tennis players (aged 22.7 ± 2.7 years). All of them were right-handed and presented an offensive style of play. Participants performed one task: performing a series of topspin strokes. Kinematic parameters were measured using the MR3 myoMuscle Master Edition system. The movement of the playing hand was used to assess specific cycle events. Angular values and velocities of the body segments and maximal linear velocities of the playing hand were calculated. The basic statistics were applied. Quartile coefficients of variation were used to assess the interindividual variability. The research made it possible to determine the kinematics of the strokes used in the combination of plays in table tennis. The essential elements of coordination of movements during the combination of three topspin strokes were indicated. Players make strokes during a series of plays at high frequency and velocity (up to several hundred degrees/s at some joints), reducing the ranges of motion in specific body segments, which were observed to be smaller (even up to several dozen degrees) than the analogous ranges reported in the literature for single strokes. This seems to be a significant note to players and coaches in table tennis. In addition, the players execute the stroke slightly differently than in single strokes, which is caused by the need to combine the striking movement with footwork and quickly position themselves for subsequent hits. The players also used different, variable execution patterns (different angles - settings in the joints), although the effect - in the form of the maximum velocity of the playing hand - was very similar. This can be considered a manifestation of a phenomenon called "functional movement variability," which means that athletes adjust their movements using different movement patterns but achieve similar results regarding maximum linear hand speed. This highlights the importance of the individualisation process in table tennis.