438 VITALITY AND EFFICIENCY WITH EESTRICTED DIET. 



The curve of H. S. does not show large changes, but there is apparent 

 the usual shortening of the pulse cycles following the stimulus of 

 walking. By the eighth cycle, the duration is again as long as during 

 the standing period, and reaches its maximum duration at the twentieth 

 cycle; subsequently it shortens slowly to 0.60 second at the sixtieth 

 cycle. At the transition from walking to standing, there does not 

 appear to be a response until the twentieth cycle, when the duration 

 increases suddenly from 0.65 to 0.73 second. By the end of the record, 

 the cycle is slower than during the preliminary standing period, and 

 in this respect it is similar to that of T. M. C. 



The average pulse-cycle duration during standing preliminary to 

 the walking transition as estimated from the curves is as follows: 

 T.M.C., 0.75; E.L.F., 0.78; H.W.F., 0.68; H.M.S., 0.84; H.S., 0.66 

 second. The values of H.W.F. and H.S. are exceptional, for the 

 corresponding pulse-rates appear to be higher by the equivalent of 

 13 and 11 beats per minute, respectively, than the rates counted during 

 the 10-minute standing period and given in table 101. (See page 449.) 

 There is, however, no known reason for the variations with these 

 subjects which would not have applied equally to the other men, both 

 in the normal group and in Squads A and B. If we accept these figures 

 for pulse-cycle durations, the changes between the values for the pre- 

 liminary standing period and the durations that occur at the apex of 

 the wave immediately following the beginning of walking range from 

 — 0.09 second for H.W.F. to 0.17 second for E.L.F., with an average 

 of 0.07 second for the group. If a comparison is also made between 

 these preliminary standing values and the durations as found from 

 the pulse-rates after 6 and 24 minutes of walking, the average pulse- 

 cycle duration appears to be 0.03 second shorter than the average 

 standing value after 6 minutes of walking and 0.05 second after 24 

 minutes. These figures include the values of H.W.F. and H.S.; 

 excluding these two, the change in the duration appears to be 0.08 

 second shorter after both 6 and 24 minutes of walking than when 

 standing. 



From the standing transition curves it is found that the average 

 pulse-cycle duration for walking immediately preceding standing is as 

 follows: T.M.C., 0.68; E.L.F., 0.65; H.W.F., 0.67; H.M.S., 0.72; H.S., 

 0.65 second. At the tenth, twentieth, and thirtieth cycles after walking 

 ceased, we find that the durations for the group have lengthened 0.03, 

 0.04, and 0.06 second, respectively. Using the preliminary standing 

 values as a basis of comparison, we find that the post-walking values 

 are, for the group, 0.04 second shorter at the tenth cycle than the pre- 

 walking values, exactly the same at the twentieth cycle, and 0.01 

 second longer at the thirtieth cycle. If we compare these sets of 

 figures with those found in a similar way for Squads A and B and 

 given on pages 431 and 435, it appears that this lengthening in the pulse- 



