BIOMECHANICAL CHANGES IN A PROFESSIONAL BASEBALL PITCHER: EARLY VS. LATE INNINGS

Abstract

The purpose of the study was to investigate the effects of extended play on the kinematic and kinetic parameters of the baseball pitch in order to gain a better understanding of injury mechanisms and preventive strategies. Four professional pitchers were videotaped with high-speed (120 Hz) cameras during the second, fourth and sixth innings of the same game. Video data were digitised for one fastball for each inning, and kinematic and kinetic parameters were calculated from the 3D coordinate data. Comparisons between the pitches were based on standard deviations found for the same parameters in a similar study of 40 professional pitchers. Shoulder and elbow ranges of motion, peak varus torque, shoulder and elbow distraction and the rates of angular velocities were among the variables to show significant change.