Carbohydrate feedings during team sport exercise preserve physical and CNS function

• Published in: Medicine and science in sports and exercise 2005-02, Vol.37 (2), p.306-315
• Main Authors: Winnick, Jason J, Davis, J Mark, Welsh, Ralph S, Carmichael, Martin D, Murphy, E Angela, Blackmon, Jill A
• Format: Article
• Language: English
• Subjects: Adult; Central Nervous System - physiology; Cognition - physiology; Dietary Carbohydrates - administration & dosage; Exercise - physiology; Exercise Tolerance - physiology; Female; Heart Rate - physiology; Humans; Male; Oxygen Consumption - physiology; Peripheral Nervous System - physiology; Physical Endurance - physiology; Psychomotor Performance - physiology; Reference Values; Space life sciences; Sports
• ISSN: 0195-9131
• DOI: 10.1249/01.MSS.0000152803.35130.A4

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. 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% VO(2max)), to running (120% VO(2max)), 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. 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). 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.