PHYSIOLOGY: ANDERSON AND LUSK 389 
Chart indicating the influence of meat and of alanin upon the energy production during mechanical 
work in the dog 
Calories of 
metabolism 
per hour 
Rest after meat, 750 grams 29 . 7 
Basal 17.2 
Difference 12.5 
Work + meat, 750 grams 92.4 
Work, no food 76.8 
Difference 15.6 
Rest + alanin, 20 grams 21. 1 
Basal 17.2 
Difference 3.9 
Work + alanin, 20 grams 82.0 
Work, no food 76 . 8 
Difference 5.2 
It is apparent that meat acts as a stimulant to metabolism, raising 
not only the level of the basal metabolism but even increasing the 
quantity of additional energy required to move the dog, above the 
quantity to be expected were there a summation between the effect of 
protein stimulation and work to be accomplished. The same holds 
true of alanin, a simple cleavage product of meat which, in metabolism, 
is convertible into lactic or pyruvic acid, either of which may be trans- 
formed into glucose. Clear and sharp cut appears the distinction be- 
tween the behavior of glucose itself and of alanin, which is convertible 
into glucose but whose intermediary acid products constitute a direct 
stimulus to metabolism, while the metabolites of glucose do not. 
Summarizing, one may conclude: 
1. Protein in the dietary is primarily for the repair of the tissues. 
It is not beneficial for the economical performance of work. In ex- 
cess, it largely increases the heat production which a working organism 
is called on to eliminate. 
2. One may reduce the basal requirement for energy by starvation, 
and this process may economize food in the case of those who do no 
mechanical work. 
3. To accomplish a given amount of work a given amount of fuel 
energy is required, irrespective of the nutritive condition of the organ- 
ism. This is of primary importance in the maintenance of armies or 
munition workers. Carbohydrate food fuel is utilized without loss. 
4. Upon the capacity for heroism in the farmer will depend in the 
immediate future the security of the world. 
