156 



METABOLISM DURING WALKING. 



measured step-lift is due to one or the other of these causes we do not 

 know. Though these differences make the measurements of less con- 

 sequence, nevertheless we believe that the values obtained have 

 enough interest to present. 



TOTAL STEP-LIFT PER MINUTE. 



A survey of the figures in tables 29 to 33 and 41 shows that for the 

 ranges of speed employed the step-lift per minute varied approxi- 

 mately from 1 to 3 meters, and that a tall man like H. R. R. had a total 

 lift per minute of about the same degree as that of a short man like 

 W. K., who had to take more steps to cover the same distance The 

 relation of speed to the step-lift is best shown by the results obtained 

 for E. D. B., with whom a larger amount of data was obtained. (See 

 table 41.) 



It may be of interest to note the average values on the basis of speed. 

 This comparison is made for E. D. B. in table 42, in which we find 

 that the average per minute step-lift at 45 meters per minute was 0.7T 

 meter; for 55 meters, 1.27 meters; for 65 meters, 1.99 meters; for 72 

 meters, 2.37 meters; and for 77 meters, 2.78 meters. 



TABLE 42. Relationship between step-lift and speed of walking in horizontal-walking experi- 

 ments without food with E. D. B. (Values per minute.) 



But of special significance is the increment in the total step-lift per 

 minute due to each meter change in speed. In passing from a speed 

 of 45 to 55 meters per minute, the total step-lift per minute increased 

 on the average for each meter increase in speed 5 cm. ; from 55 to 65 

 meters, 7.2 cm. ; from 65 to 72 meters (a change in speed of but 7 me- 

 ters), the increment was 5.4 cm.; and from 72 to 77 meters (a change 

 in speed of only 5 meters), the increase in the total step-lift was 8.2 cm. 

 per meter increase in speed. These increments per meter increase in 

 speed, which are given in table 42, show rather extraordinary irregu- 

 larity in the values. 



Finally, we should observe the step-lift per meter of distance trav- 

 eled. It is seen that at 45 meters per minute the step-lift was 1.71 



