Balance of Matter and Energy. 



531 



Glycogen katabolized. Owing to the marked losses of glycogen observed 

 during fasting, the katabolism of glycogen in food experiments following fast 

 is of especial interest. The amounts katabolized are shown in table 254. 



Table 254. Glycogen katabolized per kilogram of body-weight in metabolism 



experiments with food. 



Experi- 

 ment 

 number. 



Subject and duration of 

 experiment. 



First day. 



Total. 



Per 



kilogram 

 of body- 

 weight. 



Second day. 



Total. 



Per 

 kilogram 

 of body- 

 weight. 



Third day. 



Total. 



Per 

 kilogram 

 of body- 

 weight. 



70..., 

 72... 

 74 ... , 

 76... 



A.L.L., 1904 

 Dec. 20 to 



S.A.B., 1905 

 Jan. 11. 



S.A.B., 1905 



Feb. 2 to 

 S.A.B., 1905: 



Mar. 11 to 13. 



22. 



Grams. 

 56.46 



10.31 



27.82 

 56.37 



Average. 



37.74 



Grants. 

 0.796 



.187 



.505 



1.012 



0.625 



Grams. 

 35.95 



87.88 

 131.62 



Grams. 

 0.508 



1.586 

 2.359 



Grams. 

 99.90 



75.23 



217.47 



85.15 



1.484 130.87 



Grams. 

 1 .414 



1.351 

 3.870 



2.212 



At the end of the longer fasts the amount of glycogen katabolized was as a 

 rule not much over 15 to 20 grams per day. Hence, it is seen that on the inges- 

 tion of food in practically all instances there was a very considerable increase 

 in the katabolism of glycogen,* an increase which persisted throughout the 

 whole experiment. The largest amount katabolized on any day with food was 

 on the last day of experiment No. 76, namely, 217.5 grams. 



BALANCE OF MATTER AND ENERGY. 



In experiments with food the main comparison is that which shows in how 

 far the matter and energy of the food sustained the body and to what extent 

 material was gained or lost by the body. From the determinations of the 

 protein, fat, and glycogen katabolized and the quantities of the protein, fat, 

 and carbohydrates absorbed from the food, the gains or losses of these com- 

 pounds in the body may be determined. They are recorded in the first three 

 columns of table 255. The gain or loss of preformed water is obtained from 

 the water of food and drink and total water katabolized. This is recorded in 

 the fourth column, while in the last column the gain or loss of energy is 

 recorded. 



Although from 38 to 53 grams of protein were ingested in the food, the body 

 lost on the first day of each experiment about 30 grams of protein. This was 

 with a diet which contained practically enough energy for maintenance. On 

 the second day the loss of protein was considerably less, a decrease, in fact, of 

 more than one-half from that on the first day in all the experiments. On the 



* Carbohydrates as a whole. 



