98 ENERGY TRANSFORMATIONS DURING HORIZONTAL WALKING. 



In the experiments with food there is likewise a great decrease in the 

 heat production per unit of work when this new base-line is used. 

 Averaging the result of one period of fast walking after food on May 6 

 and those of the two periods on May 10, we find that the heat per unit 

 of work is 0.756 gram-calorie as compared with 0.907 gram-calorie, 1 

 which is the average heat-output per unit of work as computed with the 

 basal value found with the subject standing relaxed. The average 

 of 0.756 gram-calorie agrees very closely with the value of 0.739 gram- 

 calorie found in the experiment of May 11, 1914, when the subject was 

 running after the taking of food. 1 



It would thus appear that the apparent disadvantage in walking a 

 given distance at a speed of approximately 144 meters per minute as 

 compared with running is due to the type of walking commonly 

 employed by professional pedestrians and used by subject II, the extra- 

 neous movements of the arm playing an important role. 



ANALYSIS OF THE MECHANICS OF LOCOMOTION. 



The experimental data obtained in this research permit the compari- 

 son of several important factors in the mechanics of locomotion as we 

 have accurate records of the distance walked per minute, the number 

 of steps per minute and the height to which the body was raised per 



TABLE 20. Mechanics of locomotion in walking experiments with subject II. 



minute. These values for the varying conditions of walking and run- 

 ning and with and without food appear in several of the preceding 

 tables 2 and have been used as the basis for computing the values com- 

 pared in table 20. In this table the average values are given for the 

 height to which the body was raised both per minute and per step, the 

 distance walked or run per minute, the number of steps per minute, and 

 the length of the step. The comparisons are made for the values 

 obtained with the subject walking at low, medium, and high rates of 

 speed, and with the subject running, the rate of progression for the 

 latter being approximately the same as in walking at high speed. 



J See table 16. 



2 See tables 4, 13, 14, and 16. 



