There is plenty of evidence that carbohydrate and electrolyte drinks during prolonged endurance exercise can improve performance. Much less is known, though, about the potential impact of carbohydrate and electrolyte drinks on performance of the intermittent high-intensity exercise typical of team sports like football and basketball.

That gap in knowledge has now been filled to a large extent by a US study demonstrating that carbohydrate and electrolyte drinks during team sport exercise preserve both physical and central nervous system (CNS) function, so alleviating performance declines in the later stages of games.

Twenty active men and women performed two experimental trials during which they were fed either a 6% carbohydrate solution or a fluid-and-electrolyte placebo. The trials consisted of four 15-minute quarters of shuttle running at varying intensities and 40 jumps at a target positioned at 80% of maximal vertical jump height.

During each break the subjects performed a battery of tests designed to measure peripheral and CNS function, including 20m sprints, a 60s maximal jumping test, internal and external mood evaluation, and tests of cognitive function, force sensation, motor skills and target jumping accuracy.

The main findings were that, by comparison with placebo, carbohydrate and electrolyte drinks enhanced:

• performance of primarily physical tasks like sprinting and jumping;
• performance of whole body motor skills, requiring a combination of speed and agility;
• external ratings of subjects’ overall mood state late in exercise.

‘In summary,’ conclude the researchers, ‘our results suggest that carbohydrate feedings in the form of a 6% carbohydrate and electrolyte drink (approximately 41g of CHO per hour) can attenuate reductions in both physical and CNS function that occur when only fluid and electrolytes are ingested.

‘Moreover, this “protective effect” of CHO feedings occurred during that latter stages of our exercise protocol… The implications are that CHO feedings during exercise designed to mimic activity that occurs during team sports such as basketball can contribute to an athlete’s ability to perform at their highest level both mentally and physically.’

Med Sci Sports Exerc 2005, vol 37, no 2, pp306- 315