Frontiers in Bioscience-Scholar (FBS) is published by IMR Press from Volume 13 Issue 1 (2021). Previous articles were published by another publisher on a subscription basis, and they are hosted by IMR Press on imrpress.com as a courtesy and upon agreement with Frontiers in Bioscience.
*Author to whom correspondence should be addressed.
Academic Editor: Clark Blatteis
Participants in prolonged, physically demanding cold-weather activities are at risk for a condition called "thermoregulatory fatigue". During cold exposure, the increased gradient favoring body heat loss to the environment is opposed by physiological responses and clothing and behavioral strategies that conserve body heat stores to defend body temperature. The primary human physiological responses elicited by cold exposure are shivering and peripheral vasoconstriction. Shivering increases thermogenesis and replaces body heat losses, while peripheral vasoconstriction improves thermal insulation of the body and retards the rate of heat loss. A body of scientific literature supports the concept that prolonged and/or repeated cold exposure, fatigue induced by sustained physical exertion, or both together, can impair the shivering and vasoconstrictor responses to cold ("thermoregulatory fatigue"). The mechanisms accounting for this thermoregulatory impairment are not clear, but there is evidence to suggest that changes in central thermoregulatory control or peripheral sympathetic responsiveness to cold lead to thermoregulatory fatigue and increased susceptibility to hypothermia.