DISCUSSION OF RESULTS AND GENERAL CONCLUSIONS. 97 



It is impracticable inside the narrow confines of a respiration calorimeter 

 to study the metabolism of Marathon runners or a college eight-oared boat 

 crew, but a bicycle rider, riding to the limit of human endurance, has been 

 studied. 1 If we use the figures for carbon-dioxide production and oxygen con- 

 sumption determined on this professional rider, we shall be able to compute the 

 probable loss in weight from the body of the football player which was due to 

 the oxidation of organic material; by deducting this loss from the total weight, 

 we can find the loss due to the insensible and sensible perspiration. The bicy- 

 clist produced 200 grams of carbon dioxide per hour and absorbed 121 grams of 

 oxygen. Since practically all of the oxygen absorbed was immediately given 

 off in combustion products, we may infer that of the total loss in weight from 

 the body the carbon sufficient to produce 200 grams of carbon dioxide repre- 

 sents approximately the amount of organic material lost from the man's body 

 during one hour of severe muscular work, although there should also be a small 

 allowance for hydrogen. It is safe to say, therefore, that during an hour of 

 exceedingly hard muscular work, such as this strenuous football player indulged 

 in, there would be burned in the body not far from 100 grams of dry organic 

 material. This is approximately a quarter of a pound, leaving a total of 13.75 

 pounds of lost weight due to water. However, eating and drinking caused the 

 body- weight of the subject to return to normal inside of 48 hours. 



This illustration not only serves admirably to show the enormous fluctua- 

 tions that can take place in the body in a very short time, but also gives us a 

 hint as to the possible cause of sudden changes in body-weight such as may be 

 experienced inside of 24 or 48 hours, namely, that these changes in body-weight 

 must of necessity be due to changes in the water-content and not to changes in 

 the organic constituents of the body. In mild diabetes the initial loss in body- 

 weight may therefore well be due in large part to loss of water, and although 

 there may be a rapid fall in body-weight, sufficient to alarm both patient and 

 physician, it need not necessarily represent the loss of organized tissue; it may 

 simply be due to the restriction of carbohydrate during the process of getting 

 the patient sugar-free. During the initial course of the disease, therefore, 

 changes in body-weight are liable to be peculiarly deceptive, both qualitatively 

 and quantitatively, since an apparent large loss in body-weight may be due 

 exclusively to changes in water-content, with material drafts upon the organ- 

 ized tissues. After this preliminary period with marked loss in body-weight 

 has passed, it is probable that the loss is then due to tissue disintegration. 



While it is true that sudden initial changes in body-weight may reasonably 

 be ascribed to fluctuations in the water-content of the body, it nevertheless 

 remains a fact that an inevitable consequence of diabetes, especially when 

 severe, is a persistent and considerable loss in weight. Although it is difficult 

 to obtain accurate data from patients with regard to their greatest body- 

 weight in health, particularly without clothes, we have attempted in all these 

 cases to secure information with regard to this important factor. These 

 weights are given in table 115, together with the minimum weight observed by 



'Benedict and Carpenter, U. S. Dept. Agr., Office Exp. Stas. Bui. 208, 1909, p. 29. 



