228 



Metabolism of Healthy Man. 



Table 94. Carbon dioxide eliminated per kilogrammeter of work in 



experiments with N. B. 



[Amounts per hour.] 



In a series of experiments carried out in the Hygienic Institute in Berlin, 

 Wolpert 1 showed that the carbon dioxide increased 1 gram for each 300 kilo- 

 grammeters of work, and thus each kilogrammeter of work 2 corresponded to 

 0.00333 gram of carbon dioxide. These results are somewhat lower than those 

 in our experiments but fully in accord with those obtained by Katzenstein and 

 by Sonden and Tigerstedt. Wolpert has made an interesting use of these 

 figures in computing the external muscular work performed by individuals in 

 various trades and occupations. 



Oxygen consumed per Tcilogrammeter of ivorlc. Although the greatest em- 

 phasis in these experiments was laid upon the determination of carbon-dioxide 

 elimination, since practically all of these work experiments covered only 2 or 3 

 hours, we have nevertheless in some of them a reasonably accurate determina- 

 tion of oxygen. It is possible, therefore, to compute the increase of oxygen con- 

 sumption per kilogrammeter of work and thus obtain a second factor which 

 may also prove of value in interpreting the amount of external muscular work 

 performed in certain experiments in which the oxygen increment can be readily 

 determined. The results, which are given in table 95, are remarkably con- 

 cordant, even more so than with the carbon-dioxide determination, since the 

 increase in oxygen per kilogrammeter of work varied only from 0.00321 to 

 0.00353 gram, averaging, as a result of 4 experiments, 0.00342 gram. For 

 every gram of oxygen increase above the resting metabolism there was, on the 

 average, 293 kilogrammeters of work performed. The oxygen was not deter- 

 mined directly in the experiments of Sonden and Tigerstedt, but Katzenstein 

 found for every kilogrammeter of work by means of the ergostat 1.957 c. c. of 

 oxygen, corresponding to 0.00279 gram of oxygen, a value considerably lower 

 than that found by us. Similarly, Heinemann found the values for oxygen per 



1 Wolpert, Archiv f . Hygiene, 1896, 26, p. 64. 

 - Wolpert states that a brake-ergometer was used, 

 is given. 



No description of the ergometer 



