Possible Explanation for Ergogenic Effect of Carb-Protein Sports Drink
Carbohydrate-protein sports drinks have been shown to increase exercise endurance and reduce exercise-induced muscle damage. It has been proposed that these two effects may be related. Specifically, it has been suggested that carb-protein sports drinks may increase endurance by attenuating the fatigue-inducing effect of accumulating muscle damage during exercise. The results of a new study from the University of Chester, England, provide some support for this hypothesis.
Seven subjects completed an exercise bout consisting of moderate-intensity pedaling on a stationary bike followed by a five-minute time trial on two separate occasions. One session was performed in a normal, rested state and the other session was performed 48 hours after a drop-jump session designed to cause muscle damage in the legs. The subjects reported a significantly higher rating of perceived exertion during the exercise bout following the drop-jump test and also covered significantly less distance at a lower power output during the time-trial portion of that bout. The authors of the study, which was published in the European Journal of Applied Physiology, concluded, "These findings indicate that the ventilatory equivalent for oxygen and perceived exertion at submaximal work rates are increased 48 hours following eccentric exercise. Furthermore, exercise-induced muscle damage increases perceived exertion and impairs performance during a 5-minute all-out effort."
This study establishes a clear link between exercise-induced muscle damage and reduced endurance performance and thus supports the notion that carb-protein sports drinks may enhance endurance performance by reducing muscle damage. |
