When the wind-chill index plunges to 25 degrees below zero, Mary Lee Slettehaugh won't go out for her daily, half-hour walk. Otherwise, neither rain nor snow nor dark of night keeps the 40-year-old communications specialist from her appointed 1.5 miles. "It can be beautiful to walk in the snow or the rain as long as you're prepared," says Slettehaugh, who meets two friends at 5:45 each morning to walk around their Newport, Minn., neighborhood, where the annual snowfall is about 65 inches. "It's a great way to start the day and get in touch with nature."

While many self-respecting mammals use cold as an excuse to hibernate, people hooked on the pleasures of moving in fresh air know that by taking certain precautions they can continue outdoor activity in all but the harshest conditions. Try these tips to enhance your winter workouts: Dressfor cold comfort. Wear layers to trap the heat you generate. Next to your skin, wear a fabric that draws away sweat, such as polypropylene. The second layer should be warm and insulating, like wool or fleece. The outer layer should be water-repellent and wind-resistant, in a fabric such as nylon or Gore-Tex. Wear a hat or hood, since up to 60 percent of body heat can be lost through your head. Protect extremities with mittens and warm socks. In severe cold, cover your face with a ski mask or scarf and spread petroleum jelly over exposed skin. On sunny snowy days, wear sunscreen and sunglasses. Fuel up. Drink as much fluid when exercising in the cold as in the heat, but don't choose cold water. "If you're skiing, hiking or ice skating in cold weather," says Boston sports nutritionist Nancy Clark, "bring along a thermos filled with a warm soup or beverage. If you go to Norway, they give you blueberry soup, which has a high sugar content, for stamina. Decaffinated tea with honey, warm cider and hot cocoa are all good choices."

Cross-country skiers and others who are out in the cold for longer than 90 minutes should munch carbohydrate snacks to keep up their energy. "If your blood sugar gets too low, you may be more apt to stumble or fall," says Clark. Pick snacks that will taste good slightly frozen, such as fig bars, dried fruit and oatmeal raisin cookies. Walking. Wear leather walking shoes in cold weather. When it's wet, try galoshes with good treads over your shoes. Running. Consider switching to a heavier shoe with more traction if you're used to light, racing shoes. Warm up indoors, then start out into the wind to work up a sweat early and ensure that the wind is at your back when you may need an extra boost on the way home. In "iffy" weather, run in small loops close to home so you can retreat easily, if necessary. Snowshoes. One of the most popular winter sports items in Aspen, besides skis, are the new Sherpa or Redfeather brand snowshoes. "They're small and compact and fit over tennis shoes," says Sheri Sullenger, spa director at the Aspen Club. "Lots of people here use them to walk up the ski mountains." Snow shoveling. Hardly an activity most would pick for fun, snow shoveling can provide a great workout. But be careful. "After every snowfall, we always see people who get injured shoveling snow," says Kim Kimpton, a physical therapist at the Denver Orthopedic and Sports Medicine Clinic. Use good body mechanics to avoid back injury. Bend from the knees and hips, keep your back straight, shovel straight forward and lift with your legs rather than with your back. Never twist your torso to throw a load of snow off to the side. Instead, take a few steps to where you're going to deposit the snow and turn your shovel upside down. Don't overload your shovel. If the snow is deep, skim off two to three inches at a time.

Check with your doctor first if you have a history of heart disease, high blood pressure or back problems. Ice skating. Beginners should contact a local rink for instruction. Be sure skates fit snugly with one pair of lightweight socks or tights. The proper skate size is usually one-half to a full size smaller than your normal shoe size. For more information, send a self-addressed, stamped, business-size envelope to the Ice Skating Institute of America, 355 W. Dundee Rd., Buffalo Grove, Ill. 60089-3500. Beat a retreat. When it's extremely cold or slippery outdoors, exercise at home, in the gym or walk the mall.

Bodyworks appears on alternate Tuesdays.