By Bob Barnett
The Rumor: As long as you drink water while working out, the temperature is irrelevant
It's all about staying hydrated by drinking plenty of water, right?
The Verdict: Cold water might keep your core body temperature lower and allow you to exercise longer
A review of several studies revealed that people drink about 50 percent more cold or cool water compared to warm water when they exercise -- and as a result are less dehydrated. Other studies show that people who exercise in heat and humidity have a slower and lower rise in core body temperature when they drink cold rather than lukewarm water. Whether running, cycling or lifting weights, it appears cold-water drinkers are able to exercise longer without feeling exhausted.
"Sometimes when you feel really hot, you’ll feel more fatigue setting in," says Brooke Schantz, RD, a specialist in sports nutrition. "Cold water can help prevent your core body temperature from rising significantly." Sports nutritionist Nancy Clark, RD, author of "Nancy Clark’s Sports Nutrition Guidebook" says: "Cold water is more refreshing, and it cools you off a bit better."
But it's important to remember that cold water is a luxury. It's a necessity to drink water while working out -- regardless what temp it is. "Staying hydrated means you’ll have a lower heart rate and a lower body temperature. You won’t feel as tired and you’ll have better performance," says Schantz. To make sure you drink enough water, she suggests drinking a large glass (16 ounces) a couple of hours before you exercise, then a cup (8 ounces) about 10 or 20 minutes beforehand. While exercising, especially in the heat, stop for a sip at least every 15 or 20 minutes.
Of course, how much water you'll need to drink depends on how much you sweat. "For every pound you lose in sweat, you need to drink 16 to 24 ounces," she says. Since everyone is different, she often recommends that her student athletes weigh themselves after getting out of the shower -- and then after practice. Do that a few times and you’ll get a sense of how much you sweat, and thus, how much water you need to glug.
Freezing water in advance can make cold water consumption more convenient. "Some cyclists freeze a water bottle, so it melts while they’re cycling,” says Clark.
So, should you pack an icy bottle of H2O for your next exercise excursion? Sure, but if you don't have some ready to go, don't sweat it. Remember that it's the water, not it's temperature, that's really important.