HEAT PRODUCTION OF THE HUMAN BODY 



273 



studied with care at the eariiest possible 

 stage of its development. 



Note on Translation of German Monograph 

 on Submarine Medicine 



At the end of World War II the Technical 

 Section (Medical) U. S. Fleet, U. S. Naval 

 Forces, Germany, kept in touch with the 

 staff of the German Submarine Medicine 

 Research Institute after they evacuated the 

 laboratory at Carnac, France. A lengthy 

 monograph covering the work of this 

 Institute was prepared and translated. 

 "Any reserve supply of this monograph 

 remaining after the first distribution will be 

 in the possession of the Research Division, 

 Bureau of Medicine and Surgery. In- 



quiries concerning further distribution 

 should be directed to that office." 



Monograph on Submarine Medicine, 

 Edited by Dr. K. E. Schaefer. The follow- 

 ing subjects are discussed, some of them at 

 considerable length: The medical service on 

 the submarines, man and environment, 

 trace substances in the air, carbon monoxide, 

 compartment air, absorption of COo in 

 water, minerals in blood, gases in sub- 

 marines, metabolism, circulation of blood, 

 heat regulation, adaptation, experiments on 

 guinea pigs, CO2 intoxication, chnical in- 

 vestigations, effects on ears, ''Schnorchel" 

 submarines, nervous syndrome, rapid 

 method of O2 determination, skin tempera- 

 ture recording. There are numerous case 

 reports of nervous disorders. 



End of Foreword 



Heat Production of the Human Body 



The minimum heat production of the 

 human body is attained under conditions 

 of bed rest after fasting for a period of 8 to 

 10 hours. This level of heat production, 

 known as the basal metabolism, is near 40 

 kg. cal./m.Vhr. for the average male adult 

 of mature years. Variations in this basal 

 rate are associated in a systematic manner 

 with age and sex, and the expression of the 

 rate in terms of surface area reduces the 

 total heat production of individuals of dif- 

 ferent size to a comparable basis. DuBois 

 (14) has made an extended analysis of the 

 basic physiology of this process. 



The total basal heat production of an 

 adult male of average body size is near 70 

 kg. cal./hr., which represents the basal rate 

 per unit surface given above multiplied by a 

 total surface area of 1.7 m.^ If the strict 

 rest and fast conditions to which these basal 

 rates apply are altered to include the sitting 

 posture, light activity such as reading, and a 

 period of fast 2 to 3 hours in length rather 

 than 8 to 10, the metabolic rate per m.^ 

 rises to a value near 50 kg. cal./m.Vhr., or 

 85 kg. cal./hr. for the average man. This 



level of heat production (near 100 watts per 

 man) has been designated as the "met" by 

 Gagge, Burton, and Bazett (16), and has 

 been widely apphed in calculating the cloth- 

 ing insulation required by various combina- 

 tions of human heat production and 

 environmental temperature. 



Effect of Activity on Heat Production 



Physical activity is the primary factor 

 responsible for elevating total heat pro- 

 duction per man above the 100-watt level 

 (85 kg. cal./hr.) noted above as a reasonable 

 estimate for complete relaxation in the 

 sitting posture. Sherman (36) gives the 

 follo^ving values for average rates of heat 

 production associated with various kinds of 

 physical activity. 



In Table I the rates have been given in 

 basic units and also in multiples of the "met" 

 unit and in watts. The "met" unit is 

 arbitrary in nature, but it does possess the 

 advantage of expressing heat production in 

 simple multiples of a standard rest condition 

 familiar to everyone. Expression in watts 

 is not conventional, but has some advantage 

 for readers more familiar with engineering 

 than with physiological units. It permits 



