CARBOHYDRATE SUPPLEMENTATION REVIEWED
Coyle, E. F. (1991). Timing and method of increased carbohydrate intake to cope with heavy training, competition and recovery. Journal of Sports Sciences, 9, 18-37.
Recovery is governed by the length of time taken to fully restore muscle glycogen. Muscle glycogen is depleted after 2-3 hours of continuous exercise at 60-80% VO2max. Glycogen depletion can also occur after 15-20 min of very intense exercise at 90-130% VO2max. Low muscle glycogen levels increase the risk of injury.
Restoration of muscle glycogen can take 20 hours with correct diet and supplementation. Less than an optimal diet will increase recovery time.
CHO replenishment during exercise seems to be optimal at 7-8% concentration in water. However, after exercise it can be of a much higher concnetration.
Implication. For intermittent high intensity sports (e.g., soccer, hockey) the ingestion of CHO throughout the game, and during any rest period will result in muscle glycogen being restored and increased sprinting ability towards the end of the game. This will not happen when only water is consumed.
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