Effect of Repetitive Pitching on the Control of Lower Extremity Joints and Center of Mass in Collegiate Baseball Pitchers.

ABSTRACT

BACKGROUND: Repetitive motion can alter joint angles and subsequently affect the control of the center of mass (CoM). While the CoM has been studied as a fatigue indicator in various sports, the control of the whole-body CoM during repetitive pitching in baseball pitchers has not been examined. This study aimed to investigate changes in lower-extremity joint angles and CoM control in collegiate baseball pitchers after repetitive pitching. HYPOTHESIS: Baseball pitchers would exhibit significant increase in lower-extremity flexion angles, CoM position, and CoM variability after repetitive pitching. STUDY DESIGN: Descriptive laboratory study. LEVEL OF EVIDENCE Level 3. METHODS: A total of 23 pitchers from the Collegiate Baseball League were recruited. A motion analysis system was employed to assess lower-extremity joint angles and CoM position during the simulated game, while pitching accuracy and velocity were also recorded. RESULTS: The results revealed a significant forward and downward shift in CoM position (P < 0.05), along with increased CoM variability in all directions (P < 0.05) after the simulated game. Furthermore, there was a significant increase in flexion angles of the knee and hip (P < 0.05); however, pitching velocity and accuracy did not demonstrate significant changes. CONCLUSION: Repetitive pitching leads to kinematic changes that should be monitored to prevent sports injuries. CLINICAL RELEVANCE Baseball pitchers have the ability to modify the control of their CoM and angles of their lower-extremity joints to sustain their pitching performance. It is crucial to monitor compensatory strategies closely to avoid shoulder and elbow injuries among these pitchers.