On the Efficiency of Muscular Work. 



201 



case, but this is largely because of the failure of Glazebrook and Dye's 

 formula in connection with the individual weighing 43"7 kgrm., and, in any 

 event, the test is a crude one, so that no claim is made that the regression 

 formula is the better of the two). The regression equation does not lead to 

 any paradoxical negative values of heat production, but that it also is only 

 an interpolation formula is seen in the circumstance that the computed heat 

 production at rest exceeds the experimentally determined values of the heat 

 production in sedentary occupations, and, a fortiori, those of persons resting 

 in bed. 



The result, however, suggested the desirability of examining in the same 

 way other data. 



Table I. — Constants Deduced from Data of G-lazebrook and Dye's Table II 



{pp. cit., p. 313). 



1 



Heat production. 



Work. 



ilass. 





260 -042 

 6-4 '515 



34 -042 

 16 -016 



57 •542 

 6-452 



Standard deviation 



= -9735 = '9889 ^j,2h = 9 "478 



'•hm = -1493 ^jQi = -7668 ^,,2^ = 2 "379 



'■wii = - -0269 H'-wM = - -7608 g^S,, = 4-140 



For this purpose I selected the observations of Amar.* This investigator 

 also made use of a. stationary bicycle as an instrument for measuring work 

 performance. The subjects of the experiment were Algerians accustomed to 

 heavy manual labour, and the period of trial several hours. The determina- 

 tions of heat production weye much cruder than those of Macdonald, and 

 depend upon analyses of the ingredients of a diet sufficient to maintain the 

 subject in equilibrium (it would seem that constancy of weight was all that 

 was attempted to be maintained, separate balance sheets of the factors 

 involved not being, from the nature of the experiments, capable of 

 preparation) or upon the oxygen use. The heat productions, determined 

 by the two methods did not agree at all closely, and I have followed the 

 author in paying special attention to the heat values of the equilibrium 

 diets. Table III reproduces the observations, the amounts of work having 

 been converted from kUogramme-metres to thermal units. 



* ' Le Kendement de la Machine humaine,' Jules Amar, Paris, 1910. 



1 



