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Prevention of Cold Injuries During Exercise

When temperatures drop and snow begins to fall it means one thing: its time for Winter sports! In order to stay safe in cold weather environments, the American College of Sports Medicine has released this article on precautions that should be taken during this time of the year.

The most common cold related injuries include hypothermia, frostbite, cold urticaria, cold induced asthma, non-freezing cold injuries (trenchfoot, chilblains…) and acute cardiovascular events.

The human body goes through different physiological responses when exposed to cold, the first being peripheral vasoconstriction to decrease peripheral blood flow and reduces convective heat transfer between the body’s core and skin, subcutaneous fat and skeletal muscle.  When exposed repeatedly or chronically, a cold acclimatization occurs in three phases of thermoregulatory adjustment:

  • Habituation: Physiological responses to cold are less pronounced. We notice a decrease in shivering and cold induced vasoconstriction
  • Metabolic acclimatization: enhanced thermogenic response to cold
  • Insulative acclimatization: enhanced heat conservation mechanisms


  • Mild (<35°C) –  Feeling cold, shivering, signs of apathy/ataxia, social withdrawal, etc.
  • Moderate (<33°C) – Altered level of consciousness, etc.
  • Severe (<29°C) – Unconscious, changes in cardiac rhythms, etc.

Predisposing factors for hypothermia

Decreased heat production

Increased Heat Loss

Impaired Thermoregulation

Miscellaneous Clinical States

Training factors

  • Inactivity
  • Fatigue
  • Energy depletion
  • Lack of sleep


  • Hypopituitarism
  • Hypoadrenalism
  • Hypothyroidism
  • Hypoglycemia
  • Diabetes

Age (young & old)

Training factors

  • Immersion
  • Rain
  • Wet clothing from sweat
  • Wind
  • Fatigue
  • Low body fat

Age (young & old)


  • Burns
  • Psoriasis
  • Icthyosis
  • Exfoliative dermatitis
  • Sunburn


  • Emergency birth
  • Cold infusions
  • Heat illness
  • Treatment
  • Open wound
Peripheral failure

  • Trauma
  • Neuropathies
  • Acute spinal cord transection

Central failure

  • Central nervous system (CNS) lesions and trauma
  • Stroke
  • Subarachnoid hemorrhage
  • Hypothalamic dysfunction
  • Parkinson’s disease
  • Multiple sclerosis
  • Pharmacologic
  • Toxicologic
  • Drug and alcohol abuse
  • Infection
  • Renal failure


How to prevent hypothermia:

  • Analyse the exercise planned
    • Intensity, duration
    • Experience, condition, general health and nutritional status of athlete
  • Assess hazards
    • Air temperature, wind, rain, solar load, immersion, altitude
      • Provide shelter / warming facilities, Changing venues, cutting short or cancelling events, additional clothing
    • Education of athletes, coaches and medical personnel
      • Should be aware of hypothermia and other cold injuries symptoms, risk factors and prevention strategies
    • Clothing
      • Ideally 3 layers
        • Inner layer :
          • Does not absorb humidity and is in direct contact with skin
          • light weight polyesther or polypropylene
        • Middle layer:
          • Primary Insulation
          • polyester fleece or wool
        • Outer layer :
          • Weatherproofing (Repelling wind and/or rain)
          • Usually for resting periods only (Sport Specific)
    • Clothing insulation needs can vary during physical activity (ambient temperature, exercise intensity, etc.)
    • Every athlete/person should adjust clothing in lights of their personal needs
    • Avoid heat loss :
      • Head: associated with heat loss up to 50% in a resting person in -4°
        • Can be protected with knit caps, balaclavas, headbands, etc.
      • Feet: continue to perspire in the cold
        • Ideally changing socks ≥2 times a day
      • Food and fluid intake
        • Caloric requirements are generally not affected by cold exposure
        • Fluid balance:
          • Thirst is less noticeable in the cold
          • Cold-Induced diuresis: Immersion in cold water or exposure to cold air may increase urine flow rate


Frostbite involves crystallization of fluids when tissue temperatures fall below 0°C. Most commonly seen with exposed skin, hands and feet, first symptoms include numbness and ‘’wooden’’ sensation of the skin. Once rewarmed, pain usually appears as well as tingling, burning, aching, sharp pain, and decreased sensation. The color of the skin, initially red, becomes waxy white.

Predisposing factors for frostbite and other peripheral cold injuries:




Psychological stress

  • Temperature
  • Wetness
  • Exposure duration
  • Wind chill
  • Altitude
  • POLs (petroleum, oil, lubricants)
  • Contact with metals


  • Constrictive clothing
  • Inadequate clothing & shelter
  • Tight boots
  • Cramped positioning
  • Hypothermia
  • Race
  • Gender
  • Wet skin
  • Prior peripheral cold injury
  • Trauma
  • Erythrodermas
  • Hyperhidrosis
  • Hypoxia
  • Smoking
  • Energy depletion
  • Poor physical conditioning
  • Hypotension
  • Atherosclerosis
  • Raynaud’s syndrome
  • Vasospastic disorders
  • Diabetes
  • Shock
  • Vasoconstrictor drugs
  • Severe mental stress


How to prevent frostbites:

  • Exercise
    • Physical activity increases skin temperature (not significant when conditions are windy)
  • Clothing
    • Mittens/Gloves
      • Mittens provide greater protection (compared to gloves)
      • Liner gloves can be used to increase insulation and keep moisture away
      • Avoid blowing warm breath in gloves/mittens
        • could add moisture and increase risk of cold injury
      • Avoid petroleum jelly / emollients onto the skin
        • Gives false sense of warmth and security without lowering the risk of frostbite
      • Avoid tight straps and gloves
        • If wearing a backpack: should be taken off every few hours to allow better blood flow to arms and hands


  • Cold urticaria :
    • Rapid onset of itching, redness and swelling following exposure to cold. (Can lead to anaphylactic shock in extreme cases)
    • Prevention:
      • Avoid cold exposure
  • Cold-induced bronchoconstriction
    • Exercise-induced bronchoconstriction ( transient narrowing of airways caused by exercise)
    • Prevention:
      • Mouth-borne heat and moisture exchanger
      • Scarf
  • Cardio-vascular events
    • Cold exposure and exercise-cold stress can increase sympathetic nervous activity, total peripheral resistance, mean arterial pressure, cardiac work, and myocardial oxygen requirements.
    • Also, be aware that swimming in water <25°C may put patient at greater risk by masking symptoms of angina.
    • Prevention :
      • Patient Education : use caution when exercising/working in the cold and be aware of angina symptoms
      • Avoid swimming in cold water

Article: Prevention of Cold Injuries during Exercise, John W. Castellani et al. American college of Sports Medicine; Medicine & Science in Sports & Exercise. 2006; 0195-9131/06/3811-2012/0. Doi:10.1249/01.mss.0000241641.75101.64

Written by: Genevieve Rochette Gratton , MD, CCFP, Fellow in Sport & Exercise Medicine

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