Sports Drinks: Healthy or Hype?

We've all seen the commercials: Bulked-up jocks slam down a bright blue sports drink, then drive to the hoop or race across the finish line. The unstated but unmistakable message is that you, too, can become a super athlete by drinking this product.

Do sports drinks really boost athletic performance, or are such claims just marketing hype? The answer is complex.

Sports drinks are designed primarily to quickly replace water lost during strenuous activity. Water makes up about 60 percent of the body and 80 percent of the muscles. Water helps regulate body temperature through sweating and plays a key role in transporting oxygen and nutrients through the body. Water also is vital to moving waste from the body.

People generally feel thirsty after losing just 1 percent of their body weight through sweat. If water loss reaches 2 to 4 percent, performance may be affected as symptoms of dehydration set in. Sports drinks can help prevent this dehydration.

Old-fashioned alternative

However, before you start digging for change at the gym vending machine, think about this: Good, old-fashioned, free tap water is just as effective as the average sports drink at replacing most types of fluid loss.

Most people work out at a moderate pace for 60 minutes or less per session. Water does a great job of restoring fluids following workouts of this intensity. Water quickly moves from the stomach to the bloodstream and rehydrates the body without contributing unnecessary calories.

Though water adequately replaces fluids for most people, some athletes who work out more intensely may benefit from consuming these drinks. Endurance athletes who exercise for at least 60 minutes at high intensity or 90 minutes or more at moderate intensity place increased stress on their bodies. When muscles become especially taxed, they look for additional energy by tapping the body's store of carbohydrates, known as glycogen. Once glycogen is depleted, fatigue sets in.

Sports drinks are packed with carbohydrates (such as glucose, sucrose and fructose) that provide a quick burst of energy, preventing the body from needing to tap this stored glycogen. This can reduce or delay fatigue.

In addition, sports drinks contain electrolytes that replace sodium lost through sweat while also helping the body maintain adequate levels of plasma, the clear fluid portion of the blood. Minerals such as potassium found in some sports drinks also may be helpful in preventing some muscle cramping.

So, although sports drinks may provide a benefit to a minority of athletes, most people who exercise can get the same benefits from drinking water.

Drink early and often

Whether or not you consume sports drinks, it is vital to drink water regularly throughout the day to keep the body hydrated.

It is especially important to consume water prior to beginning a workout. Drink one or two cups of water -- 8 to 16 ounces (240 to 480 milliliters) -- two hours before the workout, and another one or two cups a half-hour before exercising. Exercise sessions that last longer than 30 minutes require 3 to 6 ounces of fluids every 15 to 20 minutes.

Once sweating begins, it is difficult to make up a hydration deficit during a workout. For this reason, it is not a good idea to wait until you are thirsty before taking a drink. Thirst is a sensation that indicates that the body is already becoming dehydrated.

Whether you sip water, sport drinks or both, the message is clear: Drink early and often to keep your body running in tip-top shape.

For more information on the pros and cons of water and sports drinks, see Water vs Sports Drinks.

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