ii2 SCIENTIFIC FEEDING OF ANIMALS 



increases very considerably. Experiments on men 

 have shown as much as 14-20% increase. The 

 fact of being accustomed to a certain kind of work 

 has also considerable influence, for according to 

 experiments on a man working a treadmill the 

 metabolism after twenty-two days' practice de- 

 creased by 10%, the work remaining the same ; 

 whilst after fifty-six days' practice it decreased 25%. 



