INFLUENCE OF MUSCULAR EXERTION UPON METABOLISM: 195 
both during fasting and with a daily ration of 1500 grams of lean 
meat. The results obtained were as follows: 
Number Meat Water Urine Urea 
Experiment. ae Gen | one | eee 
I of Rest 258 186 | 14.3 
eee reese eee eee ease ne Work 872 518 16.6 
Rest > 123 145 11.9 
16 ore peeeerer rer res 04| Work 527 186 12.3 
Rest 125 143 10.9 
Rest 182 | 1060 | 109.8 
Til caueve sateen tes 15004 | Work 657 | 1330 | 117.2 
Rest 140 | 1081 | 109.9 
or 412 | 1164 | 114.1 
I oa03 eee ge 1500} | Rest me | an |) aca 
The average increase of the proteid metabolism, as measured 
by the urea excreted, was in the fasting experiments 11.8 per cent. 
and in the experiments with food 4.95 per cent. The absolute 
difference in grams, however, was materially less in the fasting 
experiments, although approximately the same amount of work 
was performed in both cases. A similar experiment upon an 
older and quite fat dog while fasting showed an increase of only 
6 per cent. in the proteid metabolism. 
Subsequently Pettenkofer & Voit * made similar experiments 
upon a man, the work consisting in turning a heavy wheel provided 
with a brake. The work was performed in the respiration appara- 
tus. The results showed a large increase in the carbon dioxide 
excreted, but scarcely any effect was noted upon the excretion of 
nitrogen, as will be seen from the following table: 
Water Excreted. 
5 Carbon |__S O*7?. Number 
of Uniee, eel Tn Evapo- Taken Up ' Experi- 
anne ‘Gums, ‘| Urine, rated, Sims: ments. 
Grms. Grms. 
Fasting : 
Rest. oka wee ARG 8 12.4 716 1006 821 762 2 
Work ......... 12.3 1187 746 1777 1072 1 
Average diet : 
Rest a eRER OWES 17.0 928 1218 931 832 3 
Work .......-- 17.3 1209 1155 1727 981 2 
* Zeit. f. Biol., 2, 478. 
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