PULSE-RATE. 451 



reached its maximum and began to moderate during the first minute, 

 continuing the falUng rate into the third and fourth minutes as pre- 

 viously pointed out. A further inspection of the curves in figure 101 

 shows that this slowing of the rate begins probably within 20 seconds 

 after the walking starts, or in other words, that the pulse overshoots 

 at first the rate needed for the exercise to be performed, and after the 

 first 20 seconds begins an adjustment from the higher rate of stimulus 

 to the lower rate of requirement. 



In an earlier pubhcation^ it was stated that a lowering of the pulse- 

 rate was noted with several subjects on the change from standing to 

 walking. These results are not confirmed by the figures of table 101. 

 The fact that the rates during the 15 seconds of standing preliminary 

 to walking, as found from figure 101, are higher than the standing 

 average for the 10 minutes given in table 101, and that the rates of 

 T. M. C, H. W. F., and H. S., after walking 6 minutes (see fig. 101), 

 have fallen to approximately the preliminary standing rates suggests 

 that possibly the earlier observations were unwittingly taken at the 

 points of highest and lowest changes during this transition period. It 

 is evident that these changes have not yet been sufficiently studied and 

 that measurements of the pulse cycles over longer periods than has 

 been done in this study and the elimination, if possible, of the psychical 

 effect incident to the starting of the treadmill must be made. 



Table 102 summarizes the walking pulse data presented in the pre- 

 ceding tables, and shows the average pulse-rates for the sitting, stand- 

 ing, and walking observations, the increase in the number of beats, 

 and the percentage deviation from the average preliminary standing 

 pulse of each group. It is seen from this table that for the two normal 

 groups the change in the number of beats per minute on passing from 

 sitting to standing is 8 for the 5 normals and 7 for Squad B normal, 

 and on passing from standing to walking, both groups had an increase 

 of 9 beats. This is a change of 12 per cent in each instance for the 5 

 normals and of 10 and 11 per cent for Squad B normal. For the two 

 diet squads, the change in the number of beats on passing from sitting 

 to standing is about the same as for the normal groups, but on account 

 of the normally low initial pulse-rate of the diet squads, the percentage 

 changes are slightly higher. During the walking period the increase 

 in the pulse beats per minute is approximately twice as great for Squad 

 B 20-day as for Squad B normal, with increase in an accompanying 

 percentage change. Squad A 120-day does not show as great changes 

 as does Squad B 20-day, but is higher than the normals both in abso- 

 lute change in number of beats as well as percentage change. The 

 pulse-rate for standing 2 minutes after walking and the final sitting 

 rate do not indicate that any one group had a greater tendency to a 

 delayed return to the normal rate than another. In fact. Squad A 



^Benedict and Murschhauser, Carnegie Inst. Wash. Pub. No. 231, 1915, p. 85. 



