148 
MUSCULAR WORK 
of the lungs has been used to explain in part the after-effects of muscular 
activity upon gross metabolism. 
In three experiments with our professional subject, we determined the 
ventilation of the lungs by the spirometer recently devised in this laboratory a 
and attached to the respiration apparatus. The results, which have been 
reduced to 0° C. and 760 millimeters pressure, are given in table 130 
which shows the ventilation of the lungs per minute, together with the 
carbon dioxide expired, and the respiration-rate. The table also gives 
the length of time between the end of the work and the beginning of the next 
experiment. The first period of the experiment following work invariably 
shows an increased ventilation, but with the exception of one experiment — 
that of March 29, 1912 — the excessive ventilation had ceased 20 minutes 
after the work was over, and was no greater than it was before the work 
began. On March 29, the ventilation of the lungs continued somewhat 
above normal even 57 minutes after the work had ceased. 
Table 130. — Ventilation of lungs in respiration experiments before and 
after work with subject M.A.M. lying on the couch. 
[Volumes at 0° C. and 760 mm.] 
Date. 
Condition. 
Elapsed time 
from end of 
work to be- 
ginning of 
period. 
Carbon 
dioxide 
elimi- 
nated per 
minute. 
Ventila- 
tion of 
lungs per 
minute. 
Average 
respira- 
tion-rate. 
1912. 
Mar. 6.. 
Mar. 29. 
Mar. 29. 
Apr. 16 . 
Before work 
After work 
Before work 
After work 
Before work 
After work 
10 m 
53 m 
1 hr. 15 m,. . 
c.c. 
229 
225 
251 
225 
220 
224 
214 
236 
206 
212 
305 
230 
221 
232 
234 
207 
212 
213 
203 
203 
liters. 
7.4 
7.2 
8.6 
7.3 
7.3 
7.3 
6.0 
7.0 
6.3 
6.4 
9.3 
7.4 
7.1 
7.4 
6.4 
5.8 
6.0 
6.7 
5.9 
5.9 
21 
22 
28 
24 
24 
22 
19 
22 
21 
21 
27 
25 
22 
22 
20 
20 
21 
22 
20 
19 
20 m 
39 m 
57 m 
19 m 
1 hr. 20 m. . . 
2 hr. 14 m. . . 
Unfortunately the observations are not sufficiently extensive to admit 
of comparisons between normal individuals and well-trained athletes. The 
experiments with this subject were all made within 5 weeks of the end of the 
training period and hence do not give us any information as to whether or 
not the return to normal ventilation in so short a time was due to training; 
observations of this nature should, however, be made. The important point 
shown by the results in table 130 is that the excess ventilation was usually 
noted immediately after the work ceased, but the ventilation again became 
normal in a short time in two out of three cases. Whatever the results may be 
with dogs, it is certain that with this man the prolonged increase in metabo- 
lism following work was not accompanied by an increased ventilation of the 
lungs. 
o For a description of this spirometer and the method of obtaining the volume of respiration, see Benedict, 
Deutsch. Archiv f. klin. Med., 1912, 107, p. 172. 
