Influence of ball velocity, attention, and age on response time for a simulated catch.

PURPOSE: The ability of a baseball infielder to respond to a batted ball may provide the best defense for avoiding injury. This study investigated the response times of young athletes performing a simulated baseball-fielding task to estimate the maximum velocity with which a baseball can leave the bat and allow a player, standing 13.7 m away, to safely respond to the approaching ball. METHODS: Fifty boys and 50 girls between the ages of 8 and 16 yr participated. Baseballs were projected at the subjects who were standing in a standardized position behind a safety net. Two components of response time, reaction time and movement time, were determined using a motion capture system. The influences of baseball velocity (26.8 and 33.5 m x s(-1) and level of attention (full attention and attention splitting) on response time for a simulated baseball-fielding task were characterized. Based on the response times for each age group, the maximum exit-velocity from a baseball-bat interaction that would allow a young baseball player sufficient time to safely respond to an approaching baseball was calculated. RESULTS: The results showed that subjects had sufficient time to respond to exit-velocities from 26.8 m x s-1 (8- to 9-yr-old group) to 33.5 m x s-1 (16-yr-old group). However, the accuracy of the response was negatively affected by baseball velocity. CONCLUSIONS: If the exit-velocities seen during actual competition exceed the calculated maximum exit-velocities for these age groups, then our preliminary data suggest that modifications to the game of baseball that would reduce the actual exit-velocities and serve as an effective means to reduce the potential for serious or catastrophic injury are warranted. [ABSTRACT FROM AUTHOR]