210 METABOLISM AND GROWTH FROM BIRTH TO PUBERTY. 



in figure 26 (see page 140) for weights similar to those noted with the 

 children studied by these investigators. 



In practically every instance the measured heat, as computed on the 

 24-hour basis, is greater than the predicted heat. The one exception 

 is the value found on the third day of the observation of Birk and 

 Edelstein, when the measured heat was 47 calories per kilogram as 

 compared with our prediction of 50 calories. In all the other instances, 

 values very much higher than the predicted heat are found. This 

 would be expected, however, as the predicted heat represents only the 

 basal output, while the measured heat includes for the whole 24 hours 

 not only the basal output, but the heat due to activity when it exists, 

 and particularly that due to the stimulus from food. The predicted 

 heat for the children with body-weights of 3 to 10 kg. ranges from 

 50 to 58 calories per kilogram of body-weight. Using 55 calories as 

 an approximate average, it can be seen that the measured heat is very 

 considerably higher in most cases, although the values of Birk and 

 Edelstein are only 5 per cent higher, on the average, than the basal. 

 With Niemann's infants, the measured heat is nearly 70 per cent 

 higher in some cases. Even when the protocols indicate that the 

 child is quiet, we find great increases above the basal. It is clear, 

 therefore, that the ordinary 24-hour life of a young child results in a 

 heat production not far from 30 to 40 per cent above basal, a value 

 somewhat in excess of that noted in our two experiments previously 

 cited. 1 



Beyond the weight of 10 kg., or the age of 9 or 10 months, very 

 little has been done aside from the classic research of Sonden and 

 Tigerstedt 2 and that of Rubner. 3 Professor Carl Tigerstedt, 4 in his 

 monograph on the food intake of man, has collected the observations 

 of Hellstrom, Rubner, von Willebrand, and Sonden and R. Tiger- 

 stedt, with boys ranging from 9 to 14 years of age. Although he 

 specifically states that the activity was to a high degree reduced, no 

 claim is made for basal values and the calculated energy output is 

 consequently upon a " moderately quiet" basis. The data thus col- 

 lected are reproduced here in table 38. From these data, Tigerstedt 

 concludes that the caloric needs, computed on the basis of per kilo- 

 gram of body-weight, decrease with increasing age. He also finds the 

 same result when the computations are made on the basis of body- 

 surface area, although this is not shown with as great regularity as in 

 the case of weight. As heretofore stated, these observations were 

 made with children on a moderately quiet basis that is, the children 



1 Talbot, Am. Journ. Diseases of Children, 1917, 14, p. 25. 



2 Sonden and Tigerstedt, Skand. Archiv f. Physiol., 1895, 6, p. 1. 

 8 Rubner, Beitrage zur Ernahrung im Knabenalter, Berlin, 1902. 



4 Tigerstedt, Carl, Ueber die Nahrungszufuhr des Menschen in ihrer Abhangigkeit von Alter, 

 Geschlecht und Beruf, Helsingfors, 1915. Also published in Skand. Archiv f. Physiol., 

 1916, 34, p. 151. 



