PULSE-RATE. . 467 



observations made with Squad A, in which the basal values with low 

 diet obtained during January, when compared with those obtained 

 during February with an unrestricted diet, showed a tendency for a 

 more rapid return to normal of the pulse-rate following a definite 

 amount of physical work. 



CONCLUSIONS b:egarding pulse-rate. 



In this section we have endeavored to present as complete a picture 

 as possible of the changes in pulse-rate level occasioned by the low 

 diet with the accompanying change to a lower nutritional plane. We 

 have presented data for the basal pulse-rate with the subjects in the 

 lying position and with the subjects in the same position before riding 

 the bicycle ergometer, with the subjects sitting and standing, and 

 engaging in short periods of muscular exertion, also beginning to walk 

 on the treadmill, during a prolonged period of walking, the transition 

 following walking, and, finally, the recovery to the normal pulse-rate 

 following a standard amount of work on the bicycle ergometer. The 

 data have been presented analytically in each case and compared with 

 the normal standard. This normal standard is rather fragmentary 

 in the case of Squad A but fairly satisfactory for Squad B; in some 

 cases there are other normals with which we could compare these low- 

 diet pulse-rates. 



It would appear as proved by the standard electrocardiograms that 

 the lower pulse-rate characteristic of the low diet is not accompanied 

 by any pathological changes but is a simple difference in the pulse- 

 rate level between the condition of uncontrolled eating and the reduced 

 diet. The actual values for the pulse-rate during rest are such as have 

 never heretofore been observed with normal man, for a considerable 

 number of men showed pulse-rates of 35 and below and one subject 

 gave positive evidence of a rate of 29 on at least one day. Not only 

 was the pulse-rate per minute very perceptibly reduced by the low 

 diet, but the blood pressures have also been shown to be distinctly 

 lower during the same period. (See p. 382.) These low blood pressures 

 following diet restriction with both Squads A and B, taken in connec- 

 tion with the low pulse-rates, show clearly that the work of circulation 

 of these men made a minimum demand on metabolic activity. We 

 thus find here a most economically working heart, at least under normal 

 conditions of rest. 



During short periods of work, as in "chinning the bar" (p. 415), 

 the percentage increase occasioned by this physical exercise was prac- 

 tically the same for normal men and for those on the low diet, that is, 

 there was a simple change in pulse-level for the resting, working, and 

 recuperation pulse with these short periods of work, i. e., periods less 

 than one-half minute in length. With the pulse during work, judged 

 according to the standards which we have, it seems clear that the men 

 on reduced diet showed a greater percentage increase, as, for example, 



