Dun S, Kingsley D, Fleisig GS, Loftice J, Andrews JR. Biomechanical comparison of the fastball from wind-up and the fastball from stretch in professional baseball pitchers. Am J Sports Med 36(1):137-41, 2008.

There has been a traditional thought in the baseball community that throwing the fastball from the stretch produces greater stress on the shoulder and elbow than throwing the fastball from the wind-up. This study aimed to demonstrate if there were any significant variations in shoulder and elbow kinetics, kinematics position at front-foot contact, timing, and ball velocity between the two different throwing styles. For this study, 28 professional baseball pitchers threw fastballs from the wind up and stretch positions in a laboratory setting. A motional analysis was used to collect the data from the pitching motion of each pitcher. After analyzing the data, the results show that were are no significant differences between the two pitching styles in kinetics, timing, or ball velocity. This study provides insight that throwing from the stretch position may not result in greater stresses on the individual.

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May 13, 2009