With temperatures plummeting, it is time to take precautions against cold weather injuries.

Improper clothing, poor hydration and inadequate caloric intake are major factors in such injuries.

When an athlete's core body temperature drops below 95 degrees, the body is hypothermic. Distance runners, skiers and mountain climbers exposed to cold are susceptible to hypothermia. However even scuba divers during the summer months can be susceptible.

The temperature of the air, the temperature of the water, the wind chill, wet clothing and the length of exposure are significant factors. Also, certain drugs and medications predispose a person to cold injuries.

An athlete suffering from hypothermia may appear sluggish, apathetic, even confused and uncoordinated. The athlete's performance usually declines. Unless the hypothermia is identified early, the athlete will lose consciousness, progressing to a comatose state.

Until the athlete can be transported to a facility that properly handles cold injuries, he or she should be moved to a warm environment. Wet clothing should be removed. The athlete should be insulated with layers of clothing and blankets.

If conscious, the athlete should drink warm, sweetened fluids for internal warming of the body. If warm packs are available, these can be applied to the trunk but not to the limbs. More aggressive treatment can be initiated in a controlled setting after transfer to a hospital.

Some suggestions:

Wear a warm hat. Up to 50 percent of the body's total heat production can be lost through an unprotected head.

Fatigue is a factor in cold injuries. Eat a balanced diet of plenty of complex carbohydrates to supply adequate calories for prolonged exercising and help deter fatigue. Also drink plenty of warm fluids during cold exposure to prevent dehydration, which can increase fatigue.

Layering your clothing is recommended. The outer layer should be waterproof and windproof, protecting against wind. The inner layer, next to the skin, should insulate and help keep perspiration away from the skin. You can visit speciality ski shops for advice on proper clothing.

Alcohol does not warm the body. It increases your risk of hypothermia.

Katherine Blanchette is a medical doctor specializing in sports medicine.