224 VITALITY AND EFFICIENCY WITH RESTRICTED DIET. 



have been due to actual loss of tissue on account of continued under- 

 nourishment, with subsequent additions to the body-tissue as a result 

 of extra feeding; second, they may have been due, in part at least, 

 to variations in the amount of feces passed at different times. This 

 applies especially to one of the subjects (Pec), whose habits of defeca- 

 tion were unique in our experience. With this subject periods of 5 

 or 6 days frequently passed without defecation, while at times very 

 large quantities of feces were excreted. Finally, in spite of our pre- 

 cautions to secure an empty bladder and minimum drinking of water 

 for each subject before weighing, considerable urine may have been 

 retained. But probably the largest factor influencing the body-weight 

 was the storage of water. It was for this reason that we insisted upon 

 relatively long periods of constancj*" in weight before attaching any 

 special significance to the measurements obtained. 



Fortunately, the influence of the storage of water upon the changes 

 in body-weight gives us a good suggestion as to the character of the 

 gains in weight following the Christmas recess. Were these gains in 

 weight due to actual body-tissue, particularly fat, it would require very 

 considerable dietetic restriction and great muscular activity to reduce 

 the excess weight. It is commonly assumed that it would be extremely 

 difficult for a man to utilize 9,000 calories in one day. A man at very 

 severe muscular work is supposed to require approximately 6,000 

 calories. While these men exercised considerably after the Christmas 

 vacation, and much more than normally, their muscular activity was in 

 no wise comparable to the severe work of a Canadian lumberman, and 

 it is doubtful if their total metabolism could have reached much more 

 than 4,000 or 4,500 calories per day during this short period of excessive 

 exercise. On this basis it would require two days of pure fat combus- 

 tion to remove 1 kg. of fat from the body. As the charts show, how- 

 ever, the loss in weight with all the subjects was very rapid after the 

 return from the Christmas vacation ; hence we believe that the increases 

 in weight were more apparent than real in that they were due in large 

 part to the storage of water rather than to the addition of organized 

 tissue. This seems the more probable inasmuch as the diet commonly 

 consumed when the subjects were free from restriction contained an 

 excess amount of carbohydrate, which would tend to promote the reten- 

 tion of water in the body. This experience reminds us strongly of the 

 error Grafe^ was led into in assuming that a return to weight of a pre- 

 viously starved dog indicated complete replenishment of lost tissue. 



During the Christmas recess the men reported maximum gains in 

 weight which were, in some cases, not far from 5 or 6 kg. Pea reported 

 a gain of about 9 kg. Subject Tom was operated upon for hemor- 

 rhoids during the Christmas recess; accordingly his gain was barely 

 1 kg. Most of the men underwent strict training in the last few days 



^ See page 25 of this monograph. 



