226 Metabolism of Healthy Max. 



work performed in operations where The direct measurement is not practicable. 

 While this report, therefore, does not deal primarily with experiments on mus- 

 cular work, it is important here to point out that using the values obtained by 

 means of the bicycle ergometer and a respiration calorimeter, and the values 

 obtained with the brake ergometer or the ergostat of Johansson used in connec- 

 tion with the respiration chamber of Sonden and Tigerstedt, or the Zuntz- 

 Geppert respiration apparatus, we should find certain relationships existing 

 that may lead to generalizations of possibly considerable value in indicating the 

 amount of external muscular work performed in experiments where the carbon- 

 dioxide increment can be determined. By means of the large respiration 

 chamber of Eubner in Berlin, or of the Sonden and Tigerstedt apparatus in 

 Stockholm or Helsingfors, a number of household or commercial operations can 

 readily be studied and the carbon-dioxide increment accurately determined. 



In the report of the series of experiments carried out by Sonden and Tiger- 

 stedt, this problem has been discussed in considerable detail. In these experi- 

 ments, two kinds of work were performed; in one the subject climbed up and 

 down a ladder, in the other he rotated a brake ergometer. Since the increment 

 in the carbon dioxide eliminated was accurately measured, the authors have 

 computed the increment in the carbon-dioxide elimination per kilogrammeter 

 of work performed. The authors also studied the increment in carbon-dioxide 

 excretion which accompanied the moving of the body one pace in a horizontal 

 direction. As a result of their experiments, they conclude that there is an 

 increase in the carbon-dioxide elimination amounting to 0.000102 gram when 

 1 kilogram of body-weight is moved one pace in a horizontal direction. The 

 average length of pace of the 4 subjects used was such that the average of all 

 4 subjects showed for every kilogram of body-weight moved 1 meter in a hori- 

 zontal direction there was an increase in the carbon-dioxide elimination amount- 

 ing to 0.000149 gram. The large size of the respiration chamber in Stockholm 

 permitted an experiment of this kind. 



Katzenstein, 1 working with the Zuntz-Geppert apparatus, also found a value 

 for this factor, namely, the movement of 1 kilo of body-weight 1 meter in a 

 horizontal direction. In 4 experiments the results averaged 0.000194 gram of 

 carbon dioxide, an amount materially greater than that found with the Stock- 

 holm apparatus. 



In computing the amount of work required to raise the body on a ladder, 

 Sonden and Tigerstedt computed the height to which the body was moved and 

 the number of times the ladder was climbed, but they neglected the work of 

 going down the ladder. Neglecting this value, they found that for each kilo- 

 grammeter of work done there was an accompanying increase of carbon dioxide 

 corresponding to 0.00428 gram. Katzenstein, when studying the work of 

 ascending a mountain, found widely different results, the increase in the carbon- 

 dioxide elimination being approximately one-half that reported from the Stock- 



1 Katzenstein, Archiv f. d. ges. Physiol., 1891, 49; p. 330. 



