120 
MUSCULAR WORK 
followed by an effort to restrain himself. A superficial inspection of the ten- 
sion on the sprocket-chain bore out his assertion that there were varying 
pressures put upon the pedals during the tests. In view of the unquestionable 
inhibition on the part of the subject and the abnormal amount of internal 
muscular work, the same difficulty is found in using these values as a base- 
line as was found with the values obtained in experiments when the subject 
rode without load on a motor-driven ergometer. These abnormalities 
should be continually borne in mind in making subsequent comparisons. 
Increment in Metabolism in No-load Experiments Due to a Change from a 
Motor-driven Ergometer to Riding Without Motor. 
As has already been pointed out, when the subject is riding on the er- 
gometer without load, the legs are not in equilibrium and the actual work of 
rotation produces a considerable increase in metabolism. Furthermore, 
when the ergometer is driven by a motor, while theoretically, at least, the 
subject remains inert on the seat of the apparatus and does no work, there 
is without doubt a tendency to resist the work of the motor in driving the 
machine. Four experiments were made with the motor-driven ergometer, 
and these have been compared in table 115 with two experiments in which the 
motor was not used, the results being given on the basis of the rate of speed. 
As would be expected, when the subject rode without motor there was a 
greater metabolism than when he rode with motor, the average increase in 
the oxygen consumption being not far from 30 per cent. There was likewise 
a small increase in the pulse-rate. 
Table 115. — Metabolism in no-load experiments without food with ergometer driven by motor 
compared with metabolism in no-load experiments without motor. (Subject M. A. M.; 
ergometer II.) 
Revolutions per minute 
with no load. 
Carbon dioxide per 
minute. 
Oxygen per minute. 
Pulse-rate per 
minute. 
With 
motor. 
Without 
motor. 
No load. 
Increase 
without 
motor. 
No load. 
Increase 
without 
motor. 
No load. 
Increase 
without 
motor. 
Date. 
a 
is 
< 
Date. 
ti 
< 
■ - ~ 
3 ■• 
o o 
*3 O 
3 
o 
S 
< 

B 
o 
h 
■ 
« ti 
•O o 
"if ** 
4i . 
3 
o 
a 
< 
a 
s 
y 
■32 
El 
3 n' 
II 
i 
3 
O 
8 
< 
3 
H 
M 
■ 
ft 
1912. 
Feb. 20 
Feb. 21 
Mar. 8 
Mar. 11 
92 
96 
101 
102 
1912. 
Feb. 21 
Feb. 20 
Feb. 21 
Feb. 21 
91 
96 
98 
98 
c.c. 
503 
565 
611 
669 
c.c. 
637 
727 
771 
771 
c.c. 
134 
162 
160 
102 
26.6 
28.7 
26.2 
15.2 
c.c. 
647 
672 
743 
743 
c.c. 
817 
904 
963 
963 
c.c. 
170 
232 
220 
220 
26.3 
34.5 
29.6 
29.6 
187 
89 
95 
2 102 
99 
2 104 
2 104 
15 
10 
9 
17 
11 
10 
* There was but one record of pulse in each no-load period on this day. 
* One record of pulse. 
That the increase in the metabolism incidental to riding without motor 
when compared to riding with motor was not greater is astonishing, to say 
the least, and bears out the conviction of all the observers that with this sub- 
ject, riding without a reasonable load was a very complicated muscular pro- 
cess. In fact, it may seriously be questioned whether the values obtained 
for riding without load, both with and without motor, can properly be taken 
for a base-line in computing the efficiency. On the other hand, the increase 
in the metabolism without the motor as compared with that with the motor 
was approximately uniform, which implies a regularity in the muscular action 
