Purpose: This study was designed to examine the effect of carbohydrate (CHO) feedings on physical and central nervous system (CNS) function during intermittent high-intensity exercise with physical demands similar to those of team sports such as basketball. Methods: Twenty active men (N = 10) and women (N = 10), with experience competing in team sports, performed three practice sessions before two experimental trials during which they were fed either a 6% CHO solution or a flavored placebo (PBO). Experimental trials consisted of four 15-min quarters of shuttle running with variable intensities ranging from walking (30% [latin capital V with dot above]O2max), to running (120% [latin capital V with dot above]O2max), to maximal sprinting, and 40 jumps at a target hanging at 80% of their maximum vertical jump height. Subjects received 5 mL[middle dot]kg-1 of fluid before exercise and 3 mL[middle dot]kg-1 after exercise, in addition to 3 mL[middle dot]kg-1 over a 5-min span after the first and third quarters, and 8 mL[middle dot]kg-1 during a 20-min halftime. During each break, the subjects performed a battery of tests measuring peripheral and CNS function, including 20-m sprints, a 60-s maximal jumping test, internal and external mood evaluation, cognitive function, force sensation, tests of motor skills, and target-jumping accuracy. Results: Compared with PBO, CHO feedings during exercise resulted in faster 20-m sprint times and higher average jump height in the fourth quarter (P < 0.05). CHO feedings also reduced force sensation, enhanced motor skills, and improved mood late in exercise versus PBO (P < 0.05). Conclusion: These results suggest that CHO feedings during intermittent high-intensity exercise similar to that of team sports benefited both peripheral and CNS function late in exercise compared with a flavored placebo.
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