728 PHYSIOLOGY 



Under more normal conditions, with the increased tone of muscle 

 which is present during Waking hours, the evolution of energy by 

 the body is increased above this amount. Pettenkofer and Voit 

 found that a resting individual had an output of 2300 calories during 

 starvation and 2670 calories on a normal diet. A series of experi- 

 ments by Tigerstedt on individuals kept in a state of rest, but on 

 normal diet, gave results varying between 26 and 36 calories per kilo for 

 the twenty-four hours. We may take therefore 30 calories per kilo body 

 weight as the average requirements of a man in a state of rest. This 

 would correspond to 2100 calories for a man weighing 70 kilos. When 

 muscular work is performed the energy output is at once largely 

 increased, and with it the food requirements of the body. The 

 attempts which have been made to arrive at some idea of the average 

 amounts of food required by a working man have been based not 

 so much on scientific experiment as on an analysis and comparison 

 of the diets in general use among different classes of men, the amounts 

 of which are determined by the instinct of the man himself, while 

 its quality is limited by his daily earnings. Tigerstedt divided the 

 different diets which have been investigated into six classes, according 

 to the total amount of energy which each of them represents. These 

 are as follows : 



In view of this great variation among the diets of different 

 individuals it becomes difficult to arrive at any conclusion as to the 

 diet which should be regarded as the average and should guide us 

 in drawing up dietary scales for public institutions. Voit, from 

 experiments on ordinary workmen performing eight or nine hours' 

 labour a day, such as a bricklayer or carpenter, has laid down the 

 following as an average diet, namely : 



Protein 

 Fat . 

 Carbohydrate 



118 grm, 

 56 

 500 



