If you find yourself shivering when exercising in the cold, you could be at risk for hypothermia or frostbite and should find warmth and shelter immediately.

Frostbite is damage to the skin and underlying tissues caused by extreme cold. Early symptoms of frostbite include pain, burning, and tingling in your skin – particularly your extremities – which then turns to numbness. If caught early, frostbite will heal, but if it reaches the blood vessels, damage is permanent and can lead to gangrene and even amputation. 

Hypothermia occurs when more heat is lost than the body can generate and your body temperature becomes dangerously low - below 95°F. It is usually caused by extended exposure to the cold. Frostbite, shivering, confusion, lack of coordination, sluggishness, difficulty speaking and seeing, stumbling and muscle stiffness are all symptoms of hypothermia. 

The key to combatting cold with your clothing is to layer. Layering gives you the best control of body temperature. As you warm up, you can remove a layer or two; as you cool down, you can add them back on.

Your first layer should be soft, lightweight, and pliable, as it is closest to your skin – choose modern synthetic fibers rather than cotton or wool for this layer because they breathe better. Your second layer is for insulation, so make it your warmest – choose fleece or wool. Your outer layer should protect you from rain, wind and snow but still provide ventilation – choose a nylon windbreaker or heavier waterproof jacket.

You may be as well-wrapped as a Christmas gift from Martha Stewart, but if your extremities aren’t covered, you’ll lose significant heat from that carefully-bundled body.

When exercising outdoors, aim to have as little skin exposed as possible. Heat loss from head and neck can be as much as 50 percent of total body-heat loss, so wear a hat. If cold air causes pain when you breathe, use a scarf or mask to warm the air before it hits your throat. And don’t forget your gloves to protect your fingers from frostbite.