In a living organism 72% of energy exchange occur in the visceral organs, which comprise only 5-6% of the total body mass. The remaining energy is spent at the expense of the skin, bones, connective tissues, resting muscles. The level of energy expenditure determines the general physiological state of a human organism, serves for the diagnostics of various diseases, in particular, the diseases of endocrine system, the disruptions of thermoregulation, protein, carbohydrate, and lipometabolism, etc. It should be mentioned that in modern textbooks of physiology, pathophysiology, and biology the problem of energy exchange in humans and animals is given inadequate consideration. Traditionally it occupies only 2-2.5% of the content. Meanwhile, new problems of energy exchange have appeared recently, which almost never were advanced earlier. These are, for example, the reasons and mechanisms of high energy expenditure under conditions of metabolism, the significance of the coefficient of efficiency of a human organism in physiology, special processes previously unknown of the organism heat exchange with the environment, physiological and social components of human energy exchange. There is also a problem of a theoretical possibility of life without energy .