Enter any gym in America and you're bound to see two things, regardless of location - sweaty people and sports drinks. Beverages such as Gatorade and Powerade are everywhere, boosted by celebrity endorsements from the likes of Tiger Woods, Vince Carter and Michael Jordan. While an infusion of simple carbohydrates is undoubtedly helpful for athletes engaging in long bouts of high-intensity exercise, are sports drinks effective, or even appropriate, for the average gym-goer? Studies seem to be split on the matter.

Recently, a study indicated that the most maligned ingredients in most sports drinks, simple sugars (such as glucose and maltodextrin), were actually a key to their effectiveness, regardless of whether they were digested or not. Researchers prepared beverages containing glucose, maltodextrin or neither, so that they tasted identical, and gave them to athletes, who rinsed the drinks around in their mouths before spitting them out during exercise. Despite not reaping the energizing effects of the carbohydrates in the drinks, the rinsing of the simple sugar mixes were shown to "significantly reduce the time to complete the cycle time trial," while the placebo drinks had no such effect. The data was so impressive that the researchers concluded that "much of the benefit from carbohydrate in sports drinks is provided by signalling directly from mouth to brain rather than providing energy for the working muscle" (1).

However, simple sugars carry concerns as well, such as the risk of tooth decay. But it's not just the sugars in sports drinks that increase this risk, researchers recently concluded. The New York University School of Dentistry found that citric acid, commonly found in sports drinks, ate away at the enamel coating on teeth. As a result, the drinks could easily leak into the bone-like material underneath, causing a weakening and softening of the tooth that could "result in severe tooth damage and even tooth loss if left untreated" (2).

So should you be drinking a carbohydrate-containing beverage during your workout? There's no clear yes or no answer. If you're trying to lose weight, it's probably not the best idea, as liquid calories are unlikely to leave you sated and may negate the caloric deficit created by the exercise during which they were consumed. But even those in mass-gaining phases may find them unnecessary. Research indicates that the most important consideration may be the length of exercise.

According to researchers at the University of New Mexico, "unless a person is going to exercise for at least 90 minutes, consuming the carbohydrates is self-defeating." While sports drinks containing carbohydrates may aid the body in absorbing water, there is no evidence that the body actually retains the water more effectively than if water were consumed on its own, and therefore is not more effective at battling dehydration (3).


SOURCES:

1. Chambers, E.S. Carbohydrate sensing in the human mouth: effects on exercise performance and brain activity. The Journal of Physiology, 2009; 587: 1779-1794.

2. NYUCD Study Finds Sports Drink Consumption Can Cause Tooth Erosion. NYU Office of Public Affairs; April 7, 2009.

3. Felicia Fonseca. Study: Gatorade No Better Than Water. New Mexico Daily Lobo; March 4, 2004.