How gender and task difficulty affect a sport-protective response in young adults.

We tested the hypotheses that gender and task difficulty affect the reaction, movement, and total response times associated with performing a head protective response. Twenty-four healthy young adults (13 females) performed a protective response by raising their hands from waist level to block a foam ball fired at their head from an air cannon. Participants initially stood 8.25 m away from the cannon ('low difficulty'), and were moved successively closer in 60 cm increments until they failed to block at least five of eight balls ('high difficulty'). Limb motion was quantified using optoelectronic markers on the participants' left wrist. Males had significantly faster total response times (P = 0.042), a trend towards faster movement times (P = 0.054), and faster peak wrist velocity (P < 0.001) and acceleration (P = 0.032) than females. Reaction time, movement time, and total response time were significantly faster under high difficulty conditions for both genders (P < 0.001). This study suggests that baseball and softball pitchers and fielders should have sufficient time to protect their head from a batted ball under optimal conditions if they are adequately prepared for the task.