GASEOUS METABOLISM DURING WALKING. 533 



formity at about 0.79. Certain abnormally low respiratory quotients 

 also appear in our values, but none lower than 0.73 were used in the 

 calculation of the heat production. Those below 0.73 are as follows: 

 Bro, September 29, 0.70; Can, October 10, 0.72; Gvl, January 18, 0.72; 

 Mon, November 3, 0.68; Pec, January 7, 0.72; and Vea, October 21, 

 0.72. No simple explanation for these low values is at hand. 



From the foregoing it is seen that the respiratory quotients here 

 given have a general interest in that they show a tendency toward a 

 lowering in the katabolism of carbohydrate and probably of the 

 glycogen storage. After the unrestricted days there was invariably a 

 noticeable tendency for an increase in the respiratory quotient, indi- 

 cating a higher consumption of carbohydrate on these days. The 

 respiratory quotients in no case approach a level indicating a carbo- 

 hydrate-free diet or a state of glycogen depletion bordering upon 

 incipient acidosis. 



A practical use which was made of the respiratory quotient in this 

 research was to compute from it the calorific value of the carbon- 

 dioxide production in the experiments with the group respiration cham- 

 ber, for, as is well known, the calorific value of carbon dioxide varies 

 considerably with the respiratory quotient. The quotients obtained 

 on the days nearest to the experiments in the group respiration cham- 

 ber were used for determining the calorific value of the carbon dioxide 

 produced. 



GASEOUS METABOLISM DURING WALKING. 



The experimental procedures have made it possible to analyze the 

 basal metabolism under different conditions of nutritional level with the 

 normal and with the low diet. Furthermore, as was seen in a pre- 

 ceding section, the metabolism with both normal and reduced diet 

 was studied for the standing position, this representing a somewhat 

 greater expenditure of energy than that for the lying position, and the 

 influence of the restricted diet was found to be of practically the same 

 magnitude as that affecting the lying metabolism. The treadmill 

 experiments make it possible to study the influence of the lower nutri- 

 tional level upon a moderately active form of muscular exercise. While 

 in the lying experiments there is no voluntary muscular effort and in 

 the standing experiments the muscular effort is only slight, walking 

 approximates, to a certain extent, a great deal of the activity incidental 

 to the ordinary Hfe of most individuals not engaged in severe manual 

 labor. The walking experiments, therefore, are of particular value in 

 determining the influence of the low nutritional state upon the prob- 

 able metabolism during periods of time other than quiescent, i. e., 

 periods with a moderate amount of activity. 



In the walking experiments here discussed it was possible to measure 

 quantitatively a condition of metabolic activity involving an increase 

 in metaboHsm of over 200 per cent above the basal standing metabo- 



