Optimal Temperature for Human Life Activity

Abstract

The optimal temperature for the human life activity has been determined, by assuming that this parameter corresponds to the most intensive oxygen transport in arteries and the most intensive chemical reactions in the cells. The oxygen transport is found to be mainly governed by the blood saturation with oxygen and the blood plasma viscosity, with the both parameters depending on the temperature and the acid-base balance in blood. Additional parameters affecting the erythrocyte volume and, accordingly, the temperature of the most intensive oxygen transport are also taken into account. Erythrocytes are assumed to affect the shear viscosity of blood in the same way, as impurity particles change the suspension viscosity. It is shown that theoptimal temperature equals 36.6 ∘C under normal environmental conditions. The dependence of the optimal temperature for the human life activity on the acid-base index is discussed.