Arctic Aeromedical Laboratory. Aerospace Medical Division, Air Force Systems Command. Fort Wainwright, Alaska. Technical documentary report TDR-62-44. 29 p.
Arctic Aeromedical Laboratory. Aerospace Medical Division, Air Force Systems Command. Fort Wainwright, Alaska. Technical documentary report TDR-62-44. 29 p.
Studies were made of 10 adult male Bushmen and four Europeans during night-long exposure to ambient temperatures of approximately 6° C using only single-blanket sleeping bags . Four Bushmen were studied twice. Measurements were made of oxygen consumption, rectal and skin temperatures, muscle activity and sleep. Five Bushmen were also studied during a night with extra blankets. Rectal temperature of both groups started at about 36. 8° C, but in the Bushmen fell O. 7° C lower than in the Europeans during the cold night. Calculated mean body temperature also fell lower in the Bushmen. Mean skin temperature of the Bushmen started higher but was the same as that of the Europeans at the end of the night, although the foot temperatures of the Bushmen were lower. The heat production of both groups was the same at the start, expressed as kcal per kg lean body mass per hour (approximately 1.5). Both rose during the cold night but the Bushmen increase was only half as great as that of the Europeans . Shivering in the Bushmen was less than in the Europeans and sleep was interrupted less in the Bushmen. The results indicate a difference between Bushmen and Europeans in response to cold.