What ingredients do you really need in a sports drink?

If you’re an old-school type who thinks plain water is all you need, consider this puzzling fact: rinsing your mouth with a drink containing
carbohydrates will boost your athletic performance, even if you don’t swallow and can’t taste the carbs.
Of course, it’s not just carbohydrates that you find in sports drinks these days. The latest offerings feature a bewildering array of formulations
aimed at different sports and levels of activity, along with high-tech additives that purport to improve everything from alertness to metabolism. But
you should be wary of the hype surrounding these magic ingredients. The core of any sports drink remains simple, says University of Guelph
researcher Lawrence Spriet. Here are the three key ingredients, in order of importance:

        • FLUIDS: The first point is simple: “If you’re engaging in physical activity you’re going to lose fluids,” says Spriet, who also serves as chair of
the Gatorade Sports Science Institute’s Canadian advisory council. Although the precise link between dehydration and performance is still a
topic of debate, it’s clear that letting yourself get thirsty during exercise will compromise your performance.

        • CARBOHYDRATES: The second element is carbohydrates, which are typically found in sports drinks in the form of glucose or other easily
digested sugars. The goal is to maintain blood-sugar levels and replace glycogen stores in hard-working muscles, which is essential in bouts
of exercise lasting longer than an hour. Sports drinks traditionally contain about 6 percent carbohydrate, about half the level of a typical juice or
soft drink. That’s about as high a concentration as your stomach can handle before absorption is slowed down, according to a recent study by
University of Birmingham researcher Asker Jeukendrup in the journal Nutrition & Metabolism. Newer formulations such as Gatorade’s G2
have cut the carb level to 3 percent, which is more appropriate for people who aren’t pushing hard for hours at a time and thus don’t need the
extra calories.
Scientists have long been puzzled about why carb-filled drinks also seem to help in shorter bouts of exercise, when energy stores
shouldn’t be an issue. Researchers at the University of Birmingham published a study in 2009 showing that cyclists performed better in a time
trial if they rinsed their mouth with a drink containing either glucose or a tasteless carbohydrate called maltodextrin but saw no improvement
from rinsing with an artificially sweetened drink. Brain scans showed that glucose and maltodextrin made the reward centers in the subjects’
brains light up while artificial sweetener didn’t, suggesting that our mouths have previously unknown carbohydrate sensors. Sports scientists
have now begun advising elite athletes to rinse and spit out sports drinks as they approach the end of grueling endurance races, when their
stomachs may be unable to handle drinking anything.

                • SALTS: Electrolytes, which replace the salts lost in sweat, are thought by some researchers to play a role in muscle cramping but are more relevant to post-exercise recovery for most people. “You have to be working really, really hard for the salt to matter,” Spriet
says. Gatorade makes a little-known product called GatorLytes, which is essentially a sachet of salts that you add to regular Gatorade to up its
electrolyte content—but it’s available only to high-level sports teams, since typical athletes simply don’t need it.
For the average person working out at the gym for an hour or less at a time, there’s no need to drink anything other than water. If you prefer a
sports drink, choose one with a smaller amount of carbohydrate (3 percent is better than 6 percent), or simply dilute a standard sports drink with
water. And don’t put your faith in the magical claims of high-tech additives in some sports drinks—because beyond the three ingredients listed
above the science gets a lot weaker. In fact, Gatorade’s relaunch of its product line in the United States coincided with the decision to disband its
U.S. scientific advisory panel in 2009. The new line boasts specialized formulations such as vitamin C to perk you up in the morning, B vitamins to
help you metabolize energy, theanine to improve focus, antioxidants to “protect your body,” and so on. Spriet is unimpressed. “Everyone wants to
make things more complicated, but there’s a reason the basic formulation hasn’t changed in years,” he says. “It’s fluid, sugar, and salt. That’s all it is
—and it works!”