Adjustment of the peripheral circulation in human cold acclimatization: A critical review

The literature concerning the peripheral circulatory changes in human cold acclimatization is briefly reviewed. The warmer extremities in the cold earlier attributed to a “Metabolic acclimatization to cold” are possibly an effect of improved physical fitness, but the underlying mechanisms are still unclear. The evidence concerning a total body acclimatization to cold is equivocal. An increased hand vasoconstriction in the cold in subjects with an insulative type of acclimatization to cold may be of relatively little importance for the general thermal balance and accentuate the deteriorating effect of cold on hand functioning. There is good evidence for local manifestations of a cold acclimatization in Man: a quickened onset of an increased cold induced vasodilatation, markedly reduced or abolished cold pain and a lowered cold pressor response. The underlying mechanism is most probably a central nervous habituation to cold—possibly the main physiological mechanism in human cold acclimatization. The importance of an intact hand functioning for survival in the cold is stressed.