title: Influence of ball velocity, attention, and age on response time for a simulated catch.
abstract: OBJECTIVE
  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.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.s-1 (8- to 9-yr-old group) to 33.5 m.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.
authors.affiliation: Department of Biomedical Engineering, The Cleveland Clinic Foundation, Cleveland, OH 44195, USA. owings@bme.ri.ccf.org
authors.forename: Tammy M
authors.initials: TM
authors.lastname: Owings
authors.forename: Sarah L
authors.initials: SL
authors.lastname: Lancianese
authors.forename: Elissa M
authors.initials: EM
authors.lastname: Lampe
authors.forename: Mark D
authors.initials: MD
authors.lastname: Grabiner
mesh_terms: D000293:Adolescent; D000367:Age Factors; D001288:Attention / Q000502:physiology*; D001484:Baseball / Q000502:physiology*; D002648:Child; D015444:Exercise / Q000502:physiology; D005260:Female; D006801:Humans; D008297:Male; D011597:Psychomotor Performance / Q000502:physiology; D011930:Reaction Time / Q000502:physiology*; D012737:Sex Factors