[sidebar]Although most Americans drink plenty of fluids throughout the day, exercise time seems to be a common low-water point. “We generally replace fluids at mealtimes, and we tend to exercise hours before or after eating,” says hydration expert Michael Sawka, PhD, of the US Army Research Institute of Environmental Medicine. “Being even a little dehydrated can make you feel lethargic when you’re trying to exercise,” he says. To get the most from your workouts, top off your tank with 8 ounces of water during the hour before you exercise. This applies equally to health club classes as well as walks or runs. More from Prevention: How Much Water Do You Really Need?
