The variation of center of mass excursion within and between innings and its relationship to pitched ball velocity in collegiate softball players

The purpose of this study was to measure the changes to excursions of the COM with pitch count and innings pitched in a collegiate softball game. Additionally, the effect of excursion on pitched ball velocity was investigated. Twenty-six collegiate pitchers were recorded using a high speed video camera. The first three fastballs and the last three fastballs in each inning were used to determine the COM position during the stride foot takeoff, the lead foot touchdown, and the release. Ball velocity was also calculated from the digitization of each video. MatLab and Excel were used to calculate the excursions between the start of the pitch to the lead foot land, the lead foot land and the release and the start of the pitch and the release. The multivariate 2x5 Factorial MANOVA indicated that there was no significant interactions (F(16,532)=0.133, p=0.809) therefore main effects were investigated. There were no significant differences between the performance variables between the beginning and ending of the innings pitched (F(4,130)=0.02, p=0.99). Finally, there were no differences between innings (F(16,532)=0.99, p=0.46). The lack of support was attributed to the complex nature of the pitch with a variety of variables contributing to the execution of the pitch. The small correlation found could possibly be an increase in the arm motion and be an example of one of the many compensating factors that allow a pitcher to maintain pitched ball velocity. Future research for this topic should look at conducting the study during the spring season to reduce the variability of innings pitched, and research a younger population of athletes with the idea that in younger players the changes may be more noticeable throughout a game due to lack of strength and lower skill level