It is quite common for athletes to consume carbohydrate before, during, and after exercise. Sugar-containing beverages like Gatorade are plentiful and marketed to be the ideal beverage for athletes to optimize performance. A recent study asked the question, does adding protein to carbohydrate have any benefit over carbohydrate alone? On two occasions, eight endurance athletes performed an exercise protocol that involved 6 hours of exercise during which a supplement beverage was consumed at 30 min intervals during exercise and for 4 hours of recovery. During one exercise protocol, subjects consumed a carbohydrate beverage containing 0.7 g carbohydrate/kg/hr (about 50 g carbohydrate per hour) and during the other exercise protocol they consumed the same amount of carbohydrate combined with protein hydrolysate (0.25 g/kg/hr or about 20 g protein/hr). Rates of protein synthesis, protein breakdown, and protein balance were determined during and after exercise. Compared to the carbohydrate only trial, carbohydrate + protein resulted in significantly higher rates of protein synthesis and significantly lower rates of protein breakdown during exercise and recovery after exercise. Thus, protein balance (degradation -- synthesis) was significantly higher for the carbohydrate + protein trial. The study clearly shows the benefits of adding protein to carbohydrate on protein balance. Further, the study shows that protein and carbohydrate should not only be consumed after exercise, but ingesting protein during prolonged exercise has additional benefits on protein balance.

Koopman R, Pannemans DL, Jeukendrup AE, Gijsen AP, Senden JM, Halliday D, Saris WH, van Loon LJ, Wagenmakers AJ. Combined ingestion of protein and carbohydrate improves protein balance during ultra-endurance exercise. Am J Physiol Endocrinol Metab. 2004 Oct;287(4):E712-20. Epub 2004 May 27.