Sports exercise effect on shortening of saccadic reaction time associated with neck extensor muscle activity.

We investigated sports exercise effect on shortening of saccadic reaction time associated with neck extensor muscle activity. Saccadic reaction time was measured in neck rest position, 20 degrees neck flexion, and 30 % muscle contraction of the shoulder girdle elevators for two groups. These groups were an untrained group that has never belonged to any sports club (UT group) and a group that has belonged to high-speed ball sports clubs (HS group). In the neck flexion and 30 % muscle contraction conditions, there was a significant shortening of the reaction time for the HS group. For the UT group, no significant shortening was found in those conditions, and the reaction time in the 30 % contraction was rather significantly longer than that in the rest position. Sports experience pursuing a high-speed ball will be effective in the shortening of the saccadic reaction time associated with the activity of neck extensors.