EXPERIMENTS WITH HORIZONTAL WALKING. 



159 



For the subjects as a group, with walking at average speeds, the 

 percentage increments due to step-lift range usually from 8 to 14 per 

 cent, while with higher speeds a value for E. D. B. was found of 18 or 

 19 per cent. Benedict and Murschhauser 1 report a step-lift of 3.78 

 meters for their Subject I while he was walking at a speed of 75.9 me- 

 ters per minute. Since his body- weight was 73. 1 kg. , this corresponded 

 to a work equivalent of 276.32 kilogrammeters, or an energy require- 

 ment of 0.65 calorie per minute, which was approximately 23 per cent 

 of the total energy increment due to walking. This value is much 



TABLE 43. Effect of training on step-lift and on proportion of heat-output expended in such 

 movement. Subject, E. D. B., horizontal-walking experiments without food. October SO, 

 1915, to February 1, 1916. (Values per minute.} 



higher than that found for any of our subjects, the nearest approach 

 to it for similar speed being that for E. D. B., who, on December 1, 

 walked at a speed of 76.2 meters per minute, with a step-lift of 2.72 

 meters per minute, using 18 per cent of the heat expended for horizontal 

 progression in the step-lift. 



The effect of training on the step-lift and on the heat-output due to 

 this factor may be studied by reference to table 43, in which have been 



'Benedict and Murschhaueer, Carnegie Inst. Wash. Pub. No. 231, 1915, p. 80. 



