The Constitution is a set of functional and morphological characteristics of the organism, which determines its reactivity and established on the basis of hereditary and acquired properties. The Constitution is formed depending on environmental conditions, the important role of social factors.
In ancient times it was noticed that people differ from each other in structure of the body, temperament, functional features and predisposition to one or other influences. To this period belongs the division of people into 4 main types (choleric, sanguine, phlegmatic and melancholic).
Galen introduced the concept of habitus (see)- a set of external features that characterize the structure of the body and appearance, which linked the predisposition to various diseases; however, he believed that, in addition to the predilection, important in the event of illness is a way of life.
The modern doctrine of the Constitution is based not only on the anatomical characteristics of the organism, but also on the characteristics of its higher nervous activity, condition of the endocrine system, which determine the reactivity of the organism and its relationship with the environment.
According to the most popular in the USSR classification distinguishes three types of the Constitution - asthenic, normostenichesky and giperstenichesky. Astenikov longitudinal sizes of the body prevail over cross, limbs over the torso, chest , over his stomach; they have small internal organs and is low aperture. Giperstenikov we see the opposite picture, and normostenik occupy an intermediate position between these two types. In addition anthropometric differences (see Anthropometry), between these types Constitution has a number of physiological differences. So, astenikov compared to gipersteniki reduced blood pressure, reduced secretion and motor activity stomach, the number of erythrocytes and hemoglobin, increased metabolism, dominated by the inhibition. The function of various endocrine glands in representatives of different types can also be different.
Investigating the function of the higher functions of the brain, I. P. Pavlov has identified 4 main types of higher nervous activity. The basis for his classification were assumed power, balance and mobility of processes of excitation and braking. Selected types of I. P. Pavlov was identified with the temperaments, classification which was proposed in ancient times: 1) strong unbalanced (choleric); 2) a strong balanced mobile (sanguine); 3) a strong balanced inert (phlegmatic) and 4) weak type (melancholy). But keep in mind that very often there are mixed types of higher nervous activity only with the prevalence of symptoms of different temperament.
Typological, or constitutional, characteristics of the body are involved in the development and progression of various diseases, the nature of human behavior and should be considered in clinical practice.