Theses and Dissertations

ORCID

https://orcid.org/0009-0001-0965-1016

Advisor

Knight, Adam C.

Committee Member

Gillen, Zack M.

Committee Member

Burch, Reuben

Committee Member

Chander, Harish

Date of Degree

5-16-2025

Original embargo terms

Visible MSU Only 1 year

Document Type

Dissertation - Campus Access Only

Major

Kinesiology (Exercise Science)

Degree Name

Doctor of Philosophy (Ph.D.)

College

College of Education

Department

Department of Kinesiology

Abstract

Over 2 million people in the United States play softball alone, yet softball literature in exercise science and biomechanics is still sparse. Research that exists for softball pitching has focused on injury mechanisms and prevention, with a small portion of the literature reporting on performance. Studies have reported evidence suggesting that vertical ground reaction forces of the stride leg are related to pitch velocity. However, no studies have investigated the role of the stride leg during the initial launch phase of the pitch. Research has investigated kinematics such as pelvic and thoracic rotation during the pitch, but no research has investigated the linear or angular impulses through and about the center of mass (COM) during the pitch. Therefore, the goal of this study was to determine the role of the stride leg GRF during the launch phase and impulses through and about the COM with pitching performance. A total of 43 participants were recruited and tested in a softball facility was outfitted with 8 Qualisys cameras and 3 AMTI force plates to measure the kinematics and kinetics of the softball pitch. Kinematics were measured using Theia Markerless Motion Capture while Qualisys Track Manager was utilized to combine force plate and motion capture data. Results showed several significant correlations between pitch velocity and stride leg GRF during the beginning and end of the pitch, linear impulse through the COM at the beginning and end of the pitch, and several strength and function measurements. Further, high velocity pitchers had significantly more stride leg GRF, linear impulse through the COM, isometric strength and performed better on medicine ball throws and jump tests than low velocity pitchers. This study showed that the stride leg generates forces not only to help propel the pitcher forward but also to stop the forward momentum of the pitcher, which allows the pitcher to utilize the kinetic chain efficiently and greater forward linear impulse during launch and posterior linear impulse after foot plant is important for generating pitch velocity. Further research should continue to investigate pitching performance variables to tease out the most efficient kinematics and kinetics.

Download

Share

COinS