Toe temperatures during arctic training

Area of Science:

• Environmental Physiology
• Extreme Cold Exposure Research

Background:

• Arctic exploration and military operations expose individuals to extreme cold.
• Understanding the physiological response of extremities, specifically toes, to prolonged cold is crucial for preventing cold injury.

Purpose of the Study:

• To monitor toe surface temperature in subjects exposed to Arctic field conditions.
• To estimate the time required for toe temperature to decrease to critical levels.
• To assess the risk of cold injury during prolonged cold exposure in the Arctic.

Main Methods:

• Field monitoring of toe surface temperature in 10 subjects in Arctic Norway.
• Recording of ambient air temperatures, with a minimum of -27°C.
• Calculation of the time for toe temperature to cool from 25°C to 5°C at -21°C ambient temperature.

Main Results:

• The lowest recorded toe skin temperature was 1.9°C.
• At -21°C ambient temperature, mean time for toe temperature to cool from 25°C to 5°C was 109 minutes (SD, 10.2).
• One subject had toe temperatures below 5°C for 2.9 hours within a 27-hour period.
• No subjects showed clinical signs of cold injury, despite significant temperature drops.

Conclusions:

• Prolonged exposure to Arctic temperatures can lead to critical toe cooling.
• The absence of clinical cold injury signs does not negate the potential risk of sub-clinical damage or cold sensitization.
• Further research is needed to understand long-term effects and optimal protective strategies for extremities in extreme cold environments.