According to the researchers at the McMaster University including proteins in the sports drink and its benefit still remains controversial.
Sports drink play an important role in providing energy as it contains carbohydrates and sodium. Carbohydrates provide fuel for working muscles, and sodium maintains fluid balance in the body. The study, which is published in the August edition of Medicine & Science in Sports & Exercise, found that adding protein to a carbohydrate-electrolyte sports drink did not improve cycling time trial performance compared to the sports drink alone. The research was conducted on 10 trained cyclists who performed a simulated 80 km bicycle race on three occasions. During exercise, the subjects were given a sports drink, a sports drink supplemented with protein, or a placebo drink that provided no energy.
The drinks were similarly flavored and neither the subjects nor the researchers knew what drink was consumed during a given test. The study found that the sports drink improved performance compared to the placebo drink -- confirming prior research -- but there was no additional benefit of protein supplementation. 'Previous studies that suggested protein was beneficial used 'ride to exhaustion' tests that do not resemble normal athletic competition. In addition, the subjects in those studies received less than the optimal recommended amount of carbohydrate,' says Gibala.