EXPERIMENTS WITH SUBJECT STANDING. 115 



ture. That the temperature did not tend to rise, 1 as was the case 

 during the periods when the subject was standing motionless, would 

 indicate that the almost rigid position did tend to increase the body- 

 temperature as recorded. This might be due to the increased effort 

 made or to limitations in the radiation from the body resulting from 

 the use of a blanket, or to an effort in breathing under the conditions 

 of the period. The effort of motionless standing, therefore, seemed to 

 cause a gradual rise in temperature, but this rise was not permanent 

 and the average temperature of the succeeding periods remained very 

 much like the average of the first period. 



The curves of the body-temperature records for all of the standing 

 periods have been plotted; lack of space prevents the printing of all of 

 these, but a few typical curves have been reproduced in connection 

 with subsequent walking experiments. (See fig. 14, p. 173, and figs. 33 

 to 37, pp. 269 to 275.) The observations within the periods proper are 

 indicated by black points. The time when the subject began standing 

 is marked by the figure 2. The beginning of walking is indicated by 

 the figure 3 and of sitting by the figure 1 . The temperatures, though 

 showing some fluctuations, are fairly level for the standing portion as 

 compared with the walking portions, while each standing period shows 

 a tendency for the temperature to increase slightly, as previously 

 stated. 



BLOOD-PRESSURE WITH SUBJECT STANDING. 



To secure data on the effect upon the blood-pressure of walking at 

 various degrees of intensity, it was first necessary to obtain a base-line 

 by noting the blood-pressure of the subject while he was standing. 

 These data, which were found for E. D. B. only, are collected in 

 table 6a for the period from March 20 to the close of the study. The 

 method by which these measurements were made is described on 

 page 37. 



The blood-pressure during standing was determined on 20 days and 

 in three periods on each day, except on April 10, when there were but 

 two standing periods. The average blood-pressure for these 20 days 

 was 117 mm., and varied from 109 mm. on March 29 to 125 mm. on 

 April 8. The difference between the blood-pressures for consecutive 

 periods varied from to 5 mm., with an average variation of 3 mm. 

 Of the 20 days, there were 13 on which the pressure in the last standing 

 period was higher than the first by an average of 3.1 mm. and six days 

 on which the value for the last period was lower than that for the first 

 period by an average of 1.3 mm. ; on one day there was no change. It 

 would appear, therefore, that the effort of continued standing increased 

 the blood-pressure slightly. For the wide range between the extremes 



'It should be noted that the diurnal temperature variation curve is characterized by a tendency 

 to rise rather than fall during the forenoon, i. e., during the hours these experiments were in 

 progress. 



