Arctic medicine: Exercise in cold environments

EXERCISE IN COLD ENVIRONMENTS

Factors that affect ability to work in cold environments

  • Clothing
  • Body composition (low body fat increases risk for cold injury)
  • Health status
  • Nutrition (hypoglyceamia increases risk for cold injury)
  • Age
  • Work intensity
  • Co-morbidities such as coronary vascular disease and asthma, where inhalation of cold air triggers these diseases
  • Exacerbating special scenarios such as immersion, rain, strong wind in low ambient temperatures

COLD INJURIES

Frost bite

  • Occurs on exposed areas such as nose, cheeks, ears, chin, wrist
  • Occurs in fingers and toes
  • Occurs when cold metal objects are touched with bare skin
  • Is caused by low air temperature, wind and wetness

Calculate the cooling power of the environment by means of the Wind Chill Temperature Index (WCT-index).

  • WCT does not take into account man-made or vehicle-made wind, such as riding on the a snow skidoo
  • WCT table needs to be lowered with 10 ° if the skin is wet
  • The danger zone for frostbite starts when WCT-index is less than -27 °C
  • The risk for frostbite is less than 5% when the ambient temperature is more than -15°C

Dress for cold weather in three layers

  • Outer layer: wind breaker (waterproof)
  • Middle layer (polyester fleece or wool)
  • Inner layer (body hugger polyester or polypropelene)

Notes

  • Sweat can freeze over
  • If you wear your windbreaker and it is not windy or raining, you will sweat more, and therefore chill quicker
  • There is no standardised uniform for cold. Persons’ needs differ
  • The heavier you work, the less insulation is needed

Note

Snow shovelling can increase heart rate to its maximum capacity

  • Walking in snow  and especially over and through sastrugi utilises much more energy than walking on flat hard surfaces

Persons with coronary artery disease may not realise that they have angina when swimming in water with a temperature of less than 25°C and a myocardial infarction can be precipitated