Date of Award

Fall 2019

Document Type

Thesis Restricted

Degree Name

Master of Science (MS)



Committee Chairperson

Kenneth Clark, PhD, CSCS

Committee Member

David J. Stearne, PhD, ATC

Committee Member

Laura Pyott, MS



The Effects of Drive Line Error and Center of Mass Displacement on Pitch Velocity in Division II Male Baseball Pitchers

By: Mark Jesse

Chairperson: Kenneth Clark, PhD, CSCS

Context: Current research indicates that controlling Center of Mass (COM) translation can result in increased Pitch Velocity. Research has not been conducted on the effects of the directionality of the stride leg (Drive Line) and containment of COM medially and laterally (M-L). Objective: To examine the effects of Drive Line Error (DLE), COM M-L displacement, and Rate of loading (ROL) on Pitch Velocity. Participants: Seven Division II baseball pitchers (20.4 ± 1.13 years old, 181.4 ± 8.52 cm, 84.4 ± 6.6 kg) with no injury history participated in the study. Design and Variables: Observational study design in a controlled laboratory setting. Independent variables were DLE, COM M-L displacement, and ROL. The dependent variable was pitch velocity. Statistics: A Hierarchical linear model statistical analysis was used. Statistical significance was defined as P ≤ 0.05. Results: The hierarchical linear model revealed DLE had a significant effect on pitch velocity (p = 0.014). COM displacement was not significantly related to pitch velocity but showed moderate to strong correlation to DLE in 4 of 7 pitchers. ROL showed no significant effect on pitch velocity. Conclusion: Deviation from the drive line in either medial or lateral direction appears to have a significant effect on pitch velocity. Training pitchers to aim for the drive line with their lead leg may lead to increases in pitch velocities, potentially via containing COM M-L translation. Practicing this strategy may improve pitch mechanics efficiency and efficacy, thus providing better results for both coaches and athletes.