Finger release sequence for fastball and curveball pitches.

The purpose of this study was to determine the action of the thumb, index, and middle fingers in releasing fastballs and curveballs for nine right-handed college pitchers. Micro-switches for the fingers were created by using two strips of electroconductive tape and a ball covered with electroconductive paint. Time data, accurate to 10(-4)s, were initiated by the stride foot onto a floor mat switch. When each digit left the ball, a corresponding timer was triggered with the final channel tripped by a contact switch in the catcher's glove. A total of 103 fastball and 88 curveball trials had complete data for each of the variables studied. Results showed that for the fastball, in 91.1% of the cases, the thumb preceded the middle and index fingers by approximately 6 ms. (p less than .001) but there was no significant difference between the middle and index fingers. The curveball data indicated that five of the nine pitchers had a definite release sequence of thumb first followed by middle then index finger (p less than .001). In total, 72.7% of the curveballs thrown had a release sequence of thumb, middle, and index fingers and 24.0% had a middle, thumb, index finger release sequence. The remaining 2.3% of the pitches had either similar times or odd combinations of release sequence.