Summer's bummers

After you've weathered rain and snow, flu season, and oh-so-many months cooped up indoors, you're more than ready for some hot fun in the summertime. But before you suit up for your first swim or lace up for that first hike, remember that the hot months also bring a number of health risks for active women. Fortunately, the much-anticipated good times can be yours, as long as you head into summer prepared. Every one of these warm-weather foes is highly preventable, usually with a minimum of effort. Here's how to beat summer's hot potatoes.

Dehydration
"Dehydration is the single most important health issue in summer," says Christine Wells, Ph.D., professor emeritus of exercise science at Arizona State University. "And drinking fluids is the only answer." Start hydrating the night before you plan to be doing any outdoor exercise: at least 8 ounces the night before, and another 2 cups (16 ounces) two hours before you work out.

"Sweat rates can double in a hot, humid environment, so a woman might need to drink twice as much when she's active on a hot day," says Susan M. Kleiner, Ph.D., author of Power Eating (Human Kinetics, 1998). That means putting away at least 18 cups of fluids per day, instead of the cool-weather minimum of 9 cups. During your workout, refresh with 4-8 ounces every 20 minutes. And when you return home, drink enough to replace what you sweat out -- if you lose a pound of water weight during a run, replace it with a pint of water.

Salt tablets are useless, says Wells. But for intense workouts of more than an hour, you'll need electrolytes, the salts that help your body retain fluids. "All the sports drinks have electrolytes," she says. "Drink the one that tastes best to you."