On the mountain, common-sense precautions like wearing a helmet and not warming up on a steep chute on the first run increase your chances of ending the day happy, beer in hand at aprés-ski. But one precaution isn't so obvious: Drinking liquids. "Staying hydrated goes as far as prehab does in preventing injury, says Riggs Klika, Ph.D., director of Aspen's Carmichael Training System Performance Center and former physiologist for the U.S. Ski Team. When you're dehydrated, your blood volume decreases and so does the amount of energy-producing oxygen your muscles receive. The result? Your muscles don't have the fuel they need to perform all day, making you more likely to get injured. Based on the studies he did with elite skiers, Klika recommends sucking down up to half a gallon of weakened carbohydrate replacement drink daily (either mix half a dose of carb-heavy powder, like GU20, or cut pure Gatorade with water). "That way, you're not only getting water, he says. "You're also getting carbohydrates for energy and electrolytes like sodium, which help your muscles absorb and retain the fluids.