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% V̇O2max), to running (120% V̇O2max), to maximal sprinting, and 40 jumps at a target hanging at 80% of their maximum vertical jump height. Subjects received 5 mL·kg−1 of fluid before exercise and 3 mL·kg−1 after exercise, in addition to 3 mL·kg−1 over a 5-min span after the first and third quarters, and 8 mL·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.