Arctic Aeromedical Laboratory. Aerospace Medical Division, Air Force Systems Command. Fort Wainwright, Alaska. Technical documentary report TDR-62-22. 19 p.
Arctic Aeromedical Laboratory. Aerospace Medical Division, Air Force Systems Command. Fort Wainwright, Alaska. Technical documentary report TDR-62-22. 19 p.
Human cold adaptation was studied by comparing maximal body insulations (I values) of Korean diving women, non-diving women and men,, and of American men and women. The diving women had significantly larger I values than Korean men, due to thicker subcutaneous fat. There was no difference in I value or subcutaneous fat thickness between the diving women and the non-diving women. The Koreans had 30 per cent higher I values than Americans of comparable subcutaneous fat thickness, signifying greater vasoconstriction and a thicker shell of non-perfused tissue. The "critical water temperature" at which shivering occurred was 30° C or lower for the diving women. For other subjects of comparable fat thickness it was 31° to 34° C. This elevated shivering threshold of the diving women was the only evidence of acquired cold adaptation. The thicker subcutaneous fat of women offers more protection to cold and may be the reason why women and not men engage in diving.