82 ENERGY TRANSFORMATIONS DURING HORIZONTAL WALKING. 



three base-lines are possible, if not indeed permissible. These are, (1) 

 the average resting value with the subject standing in a relaxed posi- 

 tion, without support, which was obtained in 25 experimental days from 

 March 20 to May 14, 1914, this value being 1.25 calories per minute; 

 (2) the average resting, lying value of 51 experiments in 1911-12 by 

 Benedict and Cathcart, this being 1.17 calories per minute, referred to 

 here as lying value I ; and (3) the resting lying basal value found as an 

 average of four experimental periods on April 18, 1914, namely, 1.11 

 calories per minute, referred to here as lying value II. The subject in 

 all these experiments was without food. 



EXPERIMENTS WITHOUT FOOD. 



All of the experiments without food for subject II have been brought 

 together in table 14 and are arranged chronologically, the only dis- 

 turbance in this order being for the experiment on May 13. The change 

 in position for the experiment of May 13 was made to bring the results 

 more nearly in the order of the increasing velocity of walking. The 

 heat-output per horizontal kilogrammeter for each experiment has been 

 computed in gram calories on the three base-lines previously cited. 

 The results using a basal value obtained with the subject standing in a 

 relaxed position are given in column g; those with an average basal 

 value obtained by Benedict and Cathcart in their experiments between 

 December 7, 1911, and April 16, 1912 (lying value I), are given in col- 

 umn h; and those with a basal value obtained from the special experi- 

 ment made by Mr. L. E. Emmes on April 18, 1914 (lying value II), 

 are given in column i. Inasmuch as the values for the subject standing 

 relaxed were determined specifically for this research, and hence in 

 this particular, at least, are more appropriate than the other basal 

 values used, we shall lay great stress in our discussion upon the incre- 

 ments computed from this base-line. 



A general inspection of the values in column g shows that there is 

 a tendency towards constancy until May 4, at which time the rate of 

 walking first exceeded 100 meters per minute. Considering the 

 experiments when the speed was below 100 meters per minute, we 

 find 57 periods with speeds ranging from 56 to 93.3 meters inclusive, 

 the average speed being 71.5 meters per minute and the energy require- 

 ment for one horizontal kilogrammeter averaging 0.493 gram-calorie. 

 An inspection of the table shows considerable variation above and 

 below these average figures in isolated cases as, for instance, on April 

 15, when in one period the heat output per horizontal kilogrammeter 

 was 0.603 gram-calorie. On the other hand the value of 0.555 gram- 

 calorie is exceeded but six times and the individual values fall below 

 0.45 gram-calorie likewise only six times out of the 57 periods. It is 

 thus clear that the value 0.493 gram-calorie is distinctly representative 

 of the heat requirements for moving 1 kilogram 1 meter at speeds 

 ranging from 56 to 93.3 meters per minute. 



