454 VITALITY AND EFFICIENCY WITH RESTRICTED DIET. 



Indeed, the exertion prior to and immediately following this work was 

 also exactly the same in all cases. Previous to the riding the subject 

 lay upon a table while the basaP normal pulse-rate for that day was 

 taken ; he then made a few uniform movements in seating himself upon 

 the ergometer; after 5 minutes of riding he inmiediately lay down upon 

 the table again. The amount of work performed by each subject was 

 therefore exactly the same. This is important in interpreting the 

 differences, not only in the heart rate under the influence of work, but 

 likewise in the return to normal; also the effect of the low diet and 

 resumption of normal diet upon both the total heart rate and on the 

 rate of return to normal. After the subject had returned to the table, 

 the pulse was taken the first 15 seconds of every minute until it reached 

 the normal pulse for the day. 



PULSE-RATE BEFORE AND AFTER WORK ON BICYCLE ERGOMETER, SQUAD A. 



It is impracticable to reproduce here all of the many observations 

 obtained by Professor Johnson, these numbering several thousand, 

 but a typical day (November 23) has been selected for illustration, on 

 which all members of Squad A took the test. This day likewise repre- 

 sents the period of approximately minimum lying pulse for the entire 

 squad, as well as the minimum body-weight. The data for November 

 23 are given in table 103. The first pulse column records the average 

 of at least 3 readings prior to work; the remaining values show the 

 pulse-rate in the first 15 seconds of every minute following the work, 

 and are continued until they reach the level before work. Significant 

 features in these records are, first, the very great increase in pulse-rate 

 due to the work, that is, the heart rate increases very greatly from 

 before work, with the subject in the lying position, to immediately after 

 work, with the subject again in the lying position. The greatest 

 increase in table 103 is shown by Moy whose heart rate prior to work 

 was 41 and in the first minute after work 116. In many other instances 

 the heart rate is doubled. The headings of the columns indicate the 

 minute when the pulse-rate of each subject returned to the rate prior 

 to work. It will be seen that 4 subjects required 18 or more minutes, 

 but that 6 subjects returned to normal in 5 minutes or less.^ 



In addition to the pulse-rates given for November 23 we have 

 recorded in table 104 the pulse-rates obtained for most of the members 

 of Squad A on one of the last days with reduced diet (January 31, 1918) 

 and on four subsequent days with unrestricted diet. In these four 

 days there were pronounced changes in both body-weight and initial 

 pulse-rate. 



^ "Basal" for comparison purposes but not minimum, as all values were obtained with food. 



" The fact that in the experiments of Benedict and Cathcart the pulse after work stayed at a 

 higher level is not at variance with these findings, for it should be pointed out that Benedict and 

 Cathcart's subject worked over one hour instead of 5 minutes, and undoubtedly the metaboUsm 

 and pulse-rate were stimulated many hours after the cessation of work. 



