Effect Of Pitch Repetition On Lower Limb Joint Power During A Single Simulated Pitching Outing

Pitching requires coordinated lower limb and upper body mechanics, with the stride leg performing repeated single-leg squats and strides to the plate, often over 100 times per game. This motion demands sagittal plane joint power absorption and generation at the hip, knee, and ankle to maintain stability and contribute to pitch velocity. Lower limb muscular fatigue could attenuate joint power which could potentially lead to compensations from upper extremity muscles resulting in possible performance reduction. PURPOSE: To examine how pitch repetition affects sagittal plane joint powers in the lower limb during a simulated game. METHODS: Seven NCAA Division I pitchers (20.3 ± 1.8 yrs; 187.9 ± 6.3 cm; 92.0 ± 12.5 kg) pitched a simulated game to volitional fatigue in a laboratory setting. Data for the first and last five fastballs were recorded using an 8-camera motion analysis system and a force platform to capture 3D kinematics and GRF data. Stride leg sagittal plane joint powers were analyzed from stride leg initial contact to maximum stride knee extension. Percent differences were calculated for lower limb joint powers between the first and last five fastballs thrown. Cohen’s D Effect sizes were also calculated and described as a value of 0.2 a small effect size, 0.5 a medium effect size, and 0.8 a large effect size. RESULTS: Peak sagittal plane power absorption and generation at the ankle, knee, and hip were not different between the first and last five fastballs (Table 1). CONCLUSION: These findings suggest that lower limb joint power remains stable throughout a single simulated pitching session despite volitional fatigue. Thus, any undue stress imposed on the upper extremity to maintain pitching velocity in later innings may not be the result of compensatory adjustments of lower limb joint for power. Future research should examine cumulative fatigue over multiple sessions to better understand potential injury risks for pitchers.