88 
MUSCULAK WORK 
hydrates in the body being drawn upon for the purpose. At the completion 
of the work-period the specific katabolism incidental to muscular work 
ceases, and the picture of a body subsisting upon a depleted storage of carbo- 
hydrate material is then indicated by the lower respiratory quotient. 
INFLUENCE UPON THE BESPIRATORY QUOTIENT OF VARIATIONS IN THE AMOUNT OF 
CARBOHYDRATES IN THE DIET. 
The analysis of the figures with the subject M. A. M. can be carried 
somewhat farther by isolating a few experiments which were made with a 
semi-controlled diet. On certain days the subject was fed in the laboratory 
and given a diet which was approximately controlled. During 6 days his 
diet contained 400 or more grams of carbohydrate a day, while on 6 other days 
it was noticeably deficient in carbohydrate material, although by no means 
carbohydrate-free. The results for these particular experiments are given 
with some detail in table 94. 
Table 94. — Respiratory quotients in experiments without food following special diets. 
(Subject M. A. M.) 
Preceding diet. 
Carbohydrate-rich . 
Average 
Carbohydrate-poor . 
Average . 
Date. 
1912. 
Jan. 24 
Jan. 25 
Jan. 26 
Feb. 14 
Feb. 15 
Feb. 16 
Jan. 17 
Jan. 18 
Jan. 19 
Feb. 7 
Feb. 8 
Feb. 9 
Lying 
before 
work. 
0.87 
.80 
.86 
.87 
.81 
.87 
.85 
.77 
.77 
.77 
.84 
.81 
.79 
.70 
During 
work. 
0.87 
.92 
.83 
.93 
.95 
.90 
.87 
.74 
.74 
.91 
.86 
.82 
.82 
Lying 
after 
work. 
0.76 
.78 
.79 
.78 
.81 
.76 
.78 
.73 
.70 
.71 
.82 
.76 
.77 
.75 
The average respiratory quotient during the preliminary rest-period 
with the carbohydrate-rich diet was considerably higher than that for the 
same period with the carbohydrate-low diet, i. e., 0.85 as against 0.79. Dur- 
ing the periods with muscular work, there was a marked increase in the respira- 
tory quotient with both diets which was somewhat greater with the carbo- 
hydrate-rich diet. The low quotient after work was also observed in both 
series of experiments, the lowest quotients being found with the diet poor in 
carbohydrates. This is fully in conformity with the view previously expressed 
that during muscular work there is an excessive combustion of carbohydrates 
so that in the subsequent period the katabolism is that of a body deficient 
in glycogen. 
It is clear, therefore, that during the winter's experimentation there 
were variations in the storage of carbohydrates in the body, the relatively 
few days on which the diet was controlled giving a reasonably accurate pic- 
ture of the conditions that would be expected to exist. It is interesting to 
note that even with the carbohydrate-poor diet, when the respiratory quo- 
tients indicated low amounts of glycogen in the body, there was nevertheless 
on the average a slight increase in the respiratory quotient during work, 
