520 VITALITY AND EFFICIENCY WITH RESTRICTED DIET. 



tion apparatus, the evidence from this extensive series of experiments 

 shows that the heat per kilogram of body-weight and heat per square 

 meter of body-surface are greatly lowered, especially the latter. 



A method of comparing the metabolism of these groups of individuals 

 at different stages of their experiment which has a greater degree of 

 scientific accuracy than the earlier methods previously discussed is to 

 compare the basal metabolism as actually measured with that pre- 

 dicted by the Harris and Benedict formulae for individuals of hke age, 

 height, weight, and sex. Such a comparison has already been made 

 for the normal data in table 113 and discussed in that connection. A 

 further comparison should be made between the predicted values and 

 the results of the metabolism measurements obtained during the period 

 of minimum weight and at the end of the diet period. This is given in 

 table 133, which shows both the absolute and percentile differences as 

 found in the individual measurements with the respiratory-valve and 

 the portable respiration apparatus. The differences between the nor- 

 mal and predicted values are also included in this table for reference. 

 It is important to hear in mind that the predicted values are based upon a 

 careful biometric analysis of the metabolism data obtained with a large 

 number of individuals and are so adjusted as to give values with a reason- 

 able degree of probability for individuals of the same height, weight, age, 

 and sex} 



Practically all of the men in Squad A show much greater differences 

 between the predicted and found values at the period of minimum 

 weight than at the beginning of the experiment when they were on 

 normal diet. Thus we find that under normal conditions of diet 7 

 out of the 12 men considered show values greater than predicted. The 

 average difference for the entire squad was 1.1 per cent above the pre- 

 dicted, the striking exception being Mon, with a plus difference of 12.5 

 per cent. At the period of minimum weight-level, namely, the latter 

 part of November, all of the men, with the single exception of Mon, had 

 values considerably below those predicted. Man's metabolism was in 

 excess of the predicted values by 1.5 per cent. The average computed 

 value for the 12 men was 11.7 per cent below the predicted value. At 

 the end of the reduced-diet period every man shows a computed heat 

 production lower than the predicted value, although in the case of Mon 

 this difference is insignificant, being only 2 calories, or 0.1 per cent. 

 The average for the 1 1 men was 14.6 per cent below the predicted values. 

 It is a matter of considerable importance that throughout the entire 

 study Mon retained a consistent relationship in his total metabolism 

 not only with the rest of the squad, but with the predicted values. 

 When it is considered that we are comparing the total basal heat pro- 

 duction as actually measured by the gaseous metabolism with that 

 predicted for individuals of similar age, height, weight, and sex, as 



* Harris and Benedict, Carnegie Inst. Wash. Pub. No. 279, 1919. 



