April 25, 1919] 



SCIENCE 



407 



week was determined. The investigation 

 covered the first five weeks after enlistment 

 for Class A and the first four weeks after 

 enlistment for Class B, at the end of which 

 periods it was foimd necessary to discontinue 

 the study. Fig. 3 shows graphically the re- 

 sults obtained. The average energy value per 

 man per day of the food consumed during 

 each week is represented by a series of blocks. 

 The average weight per man was measured 

 at the beginning of each week and at the 

 end of the last week and is shown as a solid 

 line. The scales on which the two quantities 

 are plotted are shown at the left. The note- 

 worthy features of the study are the drop in 

 weight during the first week, in part presum- 

 ably a result of the typhoid prophylaxis, and 

 subsequent rise for both groups of men result- 

 ing in a net increase of 1.4 pounds per man 

 for Class A for a five-week period and 2.6 

 pounds per man for Class B for a four-week 

 period. The consumption of food in the mess 

 shows a very large increase in both cases. In 

 examining Fig. 3 it should be borne in mind 

 that up to the beginning of the third week the 

 group of recruits had not been divided into 

 Class A and Class B. 



It is of interest to compare the averages 

 for these studies with similar averages made 

 in the past. Before doing this it should be 

 stated that all of the groups reported here 

 average approximately 68 inches in height in 

 their stocking feet, and were approximately 

 25 years of age. All were K'ational Army 

 men, secured by draft from civilian life. The 

 average weight for civilians of this height 

 and age has been determined to be 145 pounds 

 in ordinary clothes.^ As the army examina- 

 tion uses stripped weight a deduction must be 

 made for the weight of the clothes. Assutming 

 six pounds as the probable value of this, 139 

 pounds may be taken as the stripped weight 

 of civilians 68 inches tall. According to this 

 standard the men of all the organizations ex- 

 cept Company A, 366th Infantry, were about 



a " Medico-actuarial Mortality Investigation," 

 Vol. I. Association of Life Insurance Medical 

 Directors and Actuarial Society of America, New 

 York, 1912. 



normal in weight at enlistment. In ordinary 

 times recruits for the regular army are drawn 

 chiefly from the laboring classes and show an 

 average weight of approximately 147 pounds 

 for the age and height of the groups here 

 .^tudied.^ The difference of seven pounds in 

 the average weight of regular army recruits 

 in peace times and these National Army men 

 is probably a result of the changed character 

 of the army due to the draft. It will be noted 

 that Company A of the 3"7th Infantry con- 

 sists of colored men ; the average weight of 

 these men at enlistment is practically that of 

 the average peace time recruits for the regular 

 army. Also the average rate of gain in 

 weight of this organization is less than in any 

 other of those here studied. With the one 

 exception just noted, all of these National 

 Army men, although they closely approximate 

 the normal civilian weight, made a consider- 

 able gain under the rather sti-enuous training 

 regime of the camp. There is no doubt that 

 this is a gain almost entirely in muscular 

 tissue. A weighted average of the increases 

 made by the three companies shown in Fig. 1 

 and of the men of the 303d Field Artillery 

 gives 6.4 pounds as the mean increase in body 

 weight for the men of the four organizations. 

 The average weight of these men after train- 

 ing (146.8 iMDunds) is about the same as that 

 of the average peace time recruit (145.1). 

 According to Munson the peace time recruit, 

 who is undoubtedly a much more robust type 

 physically than the National Army recruits, 

 gains about 2.8 pounds as a result of three 

 and a half months of military training and 

 the gain of 6.4 pounds of the National Army 

 men is thus not at all surprising. The twenty- 

 three per cent, increase in chest motility 

 shown by the men of the 303d Field Artillery 

 is scarcely second to their weight increase as 

 an index of improvement in physical condi- 

 tion. The men of this regiment showed an 

 average motility at enlistment of three inches. 

 This is a little higher than that sliown by the 



3 ' ' The Theory and Practise of Military Hy- 

 giene," E. L. Munson, New York, William Wood 

 & Co., 1901. 



