The Extremely Cold Water Perception Scale

The Extremely Cold Water Perception Scale

With the IISA 5th World Championship coming soon in Samoëns, France between January 11th – 15th and the 2023 Winter Swimming World Championships coming up in Lake Bled, Slovenia between January 23rd – 29th, there is going to be a significant number of cold water swimmers and a massive amount of news across all social media platforms this month.

If water below 16°C (61°F) is generally considered cold by most (or cool or even balmy by ice and winter swimmers), then below is one set of possibilities in describing the seven stages of cold water swimming:

First Stage of Cold Water Swimming

  • Range: 10°C – 15°C (50°F – 59°F)
  • Definition: Cold water
  • Description: Swimmer can eventually acclimatize to perform distances up to marathon swims with adequate training. Swim failure can range from 1 km to 34 km due to a very cold internal core, indicating hypothermia.   Warm clothes and a hot drink required at finish. Depending on the distance and air temperature and wind, the claw can be experience where fingers spread apart with an inability to close them. Mild hypothermia possible and may be identified by increased shivering or vasoconstriction. Severe hypothermia includes altered cognition, unusual behavior, weakness, apathy, reduced cardiac output, and even coma.

Second Stage of Cold Water Swimming

  • Range: 5°C – 10°C (41°F – 50°F)
  • Definition: Very cold water and daringly uncomfortable
  • Description: Significant discomfort is experienced throughout the entire swim in the arms with legs feeling heavy. A reduction in core body temperature leads to that heaviness feeling eventually diminished in the arms and legs. Fingers and toes get painful after a certain distance. Swim failure due to mild or severe hypothermia from 1 km to 10 km. Warm clothes, wool hat, gloves, and booties are required at finish with standard ice swimming rewarming procedures highly recommended.

Third Stage of Cold Water Swimming

  • Range: 3°C – 5°C (37.4°F – 41°F)
  • Definition: Ice cold and seriously uncomfortable 
  • Description: An initial burning sensation throughout body continues with serious discomfort experienced throughout the swim with a sharp pain in the extremities, especially in the fingers and hands. Swim failure is experienced by a maximum distance of 5 km. Experienced seconds and experienced medical personnel are required with a deep knowledge of proper rewarming procedures.  Standard ice swimming rewarming procedures are required.

Fourth Stage of Cold Water Swimming

  • Range: 1°C – 3°C or 33.8°F – 37.4°F)
  • Definition: Extremely cold and precariously uncomfortable 
  • Description: The initial and continued burning sensation and pain throughout the body continues throughout the entire swim to the point where mental facilities can become diminished quickly. Swim failure is experienced by a maximum distance of 3 km. Experienced seconds and medical staff with deep knowledge of proper rewarming procedures and acute hypothermic issues are required.

Fifth Stage of Cold Water Swimming

  • Range: 0°C – 1°C (32°F – 33.8°F)
  • Definition: Extraordinarily cold and unbearably uncomfortable during the entire swim
  • Description: The initial and continued burning sensation and pain throughout the body and head continues throughout the entire swim to the point where vision becomes impacted and mental clarity can quickly be lost.  Hands and fingers become numb and swollen and are without feeling throughout the swim.  Breathing remains labored and heavy from start to finish.  An inability to walk normally is experienced post-swim. Swim failure is experienced by a maximum distance of 2 km. Highly experienced seconds and medical staff with deep knowledge of proper rewarming procedures and acute and long-term hypothermic issues are required.

Sixth Stage of Cold Water Swimming

  • Range: -1.0°C – 0°C (30.2°F – 32°F)
  • Definition: Severely cold and painfully uncomfortable during the entire swim
  • Description: The initial and highly acute pain throughout the body and severely diminished mental acuity continues throughout the entire swim and in the post-swim experience.  There is a high risk of severe hypothermia and cardiac issues post-swim that must be assumed. Swim failure is experienced by a maximum distance of 2 km.  Hands, fingers, feet and toes immediately become – and remain immobile – and unable to function normally.  An intense mental focus is required to maintain breathing that remains significantly labored and extremely difficult throughout the swim.  Assume an inability to get out of the water and walk by oneself post-swim.  Highly experienced seconds and a medical emergency team with deep knowledge of proper rewarming procedures and acute and long-term hypothermic issues are absolutely required.

Seventh Stage of Cold Water Swimming

  • Range: sub-1.0°C (under 30.2°F)
  • Definition: Unfathomably cold and dangerously uncomfortable during the entire swim
  • Description: Highly acute and continued pain is experienced throughout the body with severely diminished mental acuity throughout the swim and in the post-swim experience. Swim failure is experienced by a maximum distance of 1.6 km. There is a very high risk of hypothermia and cardiac issues remain post-swim until the swimmer has fully recovered.  Hands, fingers, feet and toes immediately become – and remain – immobile and unable to function normally.  An intense mental focus is required to maintain breathing that remains significantly labored and extremely difficult throughout the swim.  Swimmers are incapable of getting out of the water and walk by themselves post-swim.  The highest level of experienced seconds and a medical emergency team with deep knowledge of proper rewarming procedures and acute and long-term hypothermic issues are absolutely required.

Ger Kennedy showed above in Antarctica and rewarming in a post-swim recovery room.

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Steven Munatones