The aim of this study was to examine the effect of water intake for prolonged intermittent exercise performance in the hot environment. The soccer-simulated exercise protocol consisted of a 90 min activity. This 90 min period was divided into two, 45 min identical blocks, separated by a 15 min intermission, with ten subjects divided into a control group (C group) and a water intake group (W group). W group had a 250p water intake at 15, 30 min of 1st and 2nd half. Heart rate, concentration of blood lactate, intra-ear temperature, sweat rate, RPE, and thirst level were measured. Exercise performance was evaluated from 1) shoot skill, 2) pass skill, 3) ball juggling, as technical performance, and 4) height of counter movement jump, 5) time of 30 m sprint, 6) time of shuttle running, as physical performance. Sweat rate was not different between two groups, but body weight loss was greater in the C group compared with W group. There was no difference in technical performance between two groups. Time of 30 m sprint and shuttle running were faster in the W group compared with C group. These results suggest that water intake prevents the decrease of physical performance rather than technical performance.

DESCENTE SPORTS SCIENCE Vol.23/THE DESCENTE AND ISHIMOTO MEMORIAL FOUNDATION FOR THE PROMOTION SPORTS SCIENCE