It used to be that water was the beverage of choice for athletes. But ever since 1966, when scientists from the University of Florida tested a special formula on the school's football team – the Gators – sports drinks have become a popular workout drink.
This original concoction of sugar, salt and water was appropriately named Gatorade. Over the past few decades sports drinks have come a long way with refinements in amounts of sugar and sodium, and the addition of minerals.
Recently coconut water – touted as "nature's sports drink" – has become all the rage with many celebrities and professional athletes for its hydrating properties.
But depending on your sport, these beverages might not give you a competitive edge. Before you shell out two to three dollars per 500 millilitres, you need to determine if plain water will do just as well hydrating your body.
Hydration is critical to athletic performance. In fact, dehydration is one of the most common reasons for early fatigue during exercise. All it takes is losing as little as 2 per cent of your body weight for the performance-robbing effects of dehydration to kick in.
Sweating is the body's way of releasing heat from working muscles. If you don't drink enough during exercise and you lose too much fluid from sweat, body temperature rises and performance can suffer.
The addition of sodium to sports drinks helps prevent low blood sodium (hyponatremia) in prolonged exercise. Sodium, lost along with sweat, is needed for transmitting nerve impulses and proper muscle function. Even a slight drop in blood sodium can cause problems.
Many sports drinks are made up of 6 to 9 per cent carbohydrates, in the form of liquid sugar and/or high fructose corn syrup to provide energy for working muscles. (Soft drinks and fruit juice contain 10 to 15 per cent carbohydrates.) Numerous studies have shown that the fluid, electrolytes and carbohydrates in sports drinks delay fatigue, enhance physical performance and speed recovery in athletes.
Low sugar sports drinks such as G2 Perform are popular with marathoners who get their carbohydrates from energy gels or bars during long runs and want only the fluid and electrolytes from a sports drink.
But not everyone needs to use sports drinks. If you're working out for less than an hour, water will do just fine. Sports drinks benefit people who engage in longer bouts of exercise like running, cycling and sport tournaments.
Studies also show that sports drinks can enhance the physical and mental performance of individuals who engage in team sports that are played for a short duration, but intensely.
If you're not hitting the gym, water is best to quench your thirst. Sugar-sweetened sports drinks contain calories – about 130 calories per 500 ml – that add up if you're not burning them off. And most of us don't need the extra sodium and refined sugar.
What about coconut water? Compared with most sports drinks, it's lower in calories (45 to 60 calories per 250 ml), carbohydrates and sodium, and higher in potassium, another mineral that gets sweated out during exercise. Coconut water, the juice of young green coconuts, also contains magnesium and calcium.
Coconut water shouldn't be confused with coconut milk, a high fat liquid that comes from grated coconut meat.
But coconut water fails as a good sports drink for people who engage in vigorous exercise that produces a lot of sweating, according to a report presented this past week in Philadelphia at the annual meeting of the American Chemical Society,
Coconut water's claim to fame is its high potassium content, a mineral many people don't get enough of because they don't eat enough fruits and vegetables. But during prolonged exercise, we lose much more sodium than potassium. The report concluded that coconut water alone can't replace the sodium lost during strenuous exercise.
Lighter exercisers, however, will do fine to rehydrate with coconut water or plain water.
Tennis player John Isner, who played the longest tennis match in history at Wimbledon in 2010, credits his endurance on the court to coconut water mixed with sea salt. (He mixes it with protein powder postmatch.)
Whether you hydrate with water, a sports drink, or coconut water the key is to drink enough fluids before, during and after exercise. This might sound like an easy task, yet research indicates that many athletes fall short.
Two hours before exercise, drink 500 ml of cool fluid. During exercise, keep a water bottle handy and drink 125 to 250 ml every 15 to 20 minutes. Drink even if you don't feel thirsty. When exercising longer than one hour, a sports drink is recommended. Use the alarm on your wristwatch to remind you when it is time to take a drink.
After exercise, replenish the fluid you lose through sweat. Learn how much sweat you lose during exercise by weighing yourself before and after a workout. For every pound of weight you lose during exercise, drink roughly 500 ml of fluid to rehydrate. It's also important to replenish your muscles with carbohydrates and proteins from foods or a sports recovery drink.
If you're physically active outdoors in hot, humid weather your fluid requirements will be markedly increased.
If you're a non-exerciser, stick with plain water and save sports drinks for the purpose they were intended – hydration during and after exercise.
Leslie Beck, a registered dietitian, is the National Director of Nutrition at BodyScience Medical. She can be seen every Thursday at noon on CTV NewsChannel's Direct.
Leslie Beck