Hypothermia Temperature in conjunction with wind chill and dampness or wetness can increase chances of hypothermia Most activity allows for adequate heat production (increased metabolism) and dissipation, allowing for sufficient functioning Cold weather vs. nature of particular sport Impact on warm-up and “down time”

65% of body heat is lost through radiation (head and neck 50%) 20% through evaporation 2/3 through skin and 1/3 through respiration Drop in core stimulates shivering but stops after temp. drops below 85-90oF Problems arise when heat lost exceeds heat production via metabolism Results in impairment of neuromuscular function Death is imminent when temp falls below 77-85oF.

Prevention Waterproof and windproof fabrics that allow passage of heat and sweat and allow movement Apparel geared for weather to provide semitropical microclimate for body and prevent chilling Layers and adjusting them are key to maintaining body temperature (during period of (in)activity) Inadequate clothing, improper warm-up and chill factor can lead to injury, frostbite, chilblains, and/or minor respiratory problems Be aware of hydration levels as well to enhance blood volume and heat maintenance

Common Cold Injuries Localized cooling can result in tissue damage Formation of ice crystals between cells, destroys cells, disrupts blood flow, clotting may occur Frost nip Involves, ears, nose, chin, fingers, and toes Occurs with high wind and/or severe cold Skin appears firm with cold painless areas that may peel and blister (24-72 hours) Treat with firm pressure, blowing warm air or hands in armpits (if fingers involved) Do not rub

Frostbite Chilblains result from prolonged exposure causing redness and swelling, tingling pain in toes and fingers Appears pale, hard, cold and waxy Due to poor peripheral circulation Superficial Frostbite involves only skin and subcutaneous tissue When re-warming the area will feel numb, then sting and burn It may blister and be painful for several weeks Deep Frostbite indicates frozen skin requiring hospitalization Rapid re-warming is necessary (100-110oF) Tissue will become blotchy red, swollen, painful and may become gangrenous