Lower extremity coordination variability and motor control during tennis lateral recovery: The role of forehand...

The primary objective of this research is to examine variations in lower extremity segmental coupling coordination variability (CV) during the recovery phase following a tennis stroke, specifically comparing open, semi-open, and neutral stances.

This study evaluated 14 advanced male players performing forehand strokes and lateral recoveries across these stances. Kinematic data from a motion capture system and a modified vector coding technique were used to calculate segmental CV of eight lower extremity coupling pairs during brake and push-off phases.

A one-way repeated measures analysis of variance and one-dimensional statistical parametric mapping analysis revealed that stances significantly alter coordination strategies. During the push-off phase, the open stance exhibited significantly higher CV in pelvis sagittal vs thigh sagittal coupling compared to the semi-open stance (P < 0.05, d = 0.78). Furthermore, during the 57.5-61.3% period of this phase, thigh sagittal vs shank frontal coupling CV was significantly lower in the open stance.

These findings indicate that open stance recovery utilizes unique coordination strategies, characterized by increased pelvis-thigh and decreased thigh-shank CV. From a motor control perspective, reduced distal variability likely stabilizes the knee for optimal lateral force transmission. Conversely, the increased proximal variability likely serves as a compensatory mechanism to facilitate rapid trunk repositioning and maintain dynamic balance. Ultimately, this task-specific trade-off between distal stability and proximal flexibility highlights the movement efficiency of advanced tennis players.