If you're one of those people who just can't stand to exercise indoors no matter how low the mercury goes, make sure you protect yourself from the dangers of cold-weather exposure. 

  In addition to warming up your muscles before heading out into the cold, take care to ensure that your clothing is adequate to keep your muscles warm once you're out in the frigid air. 

  Because loss of body heat is the main concern in cold-weather workouts, you should layer your clothing appropriately. Warm air is trapped between the layers of your clothing, which keeps you warmer than if you wore a bulky sweatshirt as your only layer. Here is some advice on what to wear.

• Layer one. Wear clothes made of a synthetic fiber such as polypropylene directly next to your skin because it helps pull the excess perspiration away from your body. Cotton fabrics tend to lose their insulating properties once they get wet.
• Layer two. Over this synthetic layer, wear a sweatshirt or sweater.
• Layer three. Top it all off with a windbreaker to help prevent the cold wind from disturbing the insulating layers of warm air. If you get hot, you can always take the jacket off and tie it around your waist. 

   Finally, protect your fingers, toes and face from frostbite if the temperature drops below freezing. Mittens will provide more warmth than a pair of gloves. Wear two pair of socks — one thin (next to your body) and one thick for the outer layer. Use earmuffs or a headband and a scarf to cover your ears and mouth. And, last but not least, to prevent chapping, protect the uncovered areas of the body with a petroleum-based product or vitamin-enriched moisturizer .