Kakitsuba N, Mekjavic I B
Aviat Space Environ Med. 1987 Apr;58(4):301-7.
The rate of body heat storage (S) is often used as an index of thermal stress. The traditional approach for determining S assumes that the specific heat (Cp) of all body tissues may be averaged to 0.83 kcal X kg-1 X degrees C-1, irrespective of the actual proportion of different tissues in the body. The present theoretical analysis primarily partitions the body into N compartments. However, this analytical approach involves the difficulty of making an exact evaluation of the mass and temperature of multiple compartments. Therefore, by adopting a two-compartment (core and shell) model, the specific heat capacities, mass fractions, and changes in the temperatures of the two compartments are combined, and S is defined as a function of adiposity (= mass fraction of peripheral tissues). Evaluation of a newly developed equation showed close agreement with observations during a series of cold-water immersion trials, and indicated that the new approach seems to adequately predict S as related to body composition.
