Posture: features of studying and assessing the human posture

Currently, one of the indicators of the socio-economic development of modern society is the life expectancy of citizens, which largely depends on the state of health, physical activity and physical education. Unfortunately, in recent years in Ukraine there have been trends in the reduction of the basic health indicators of the population, especially children and youth. As the statistics show, today 80% of schoolchildren have significant deviations in physical development. At the same time, the number of people regularly engaged in physical culture and sports is sharply reduced.

Posture disorders represent one of the most pressing problems of child health. These disorders occur, as a rule, because of the irrational movement of children and create unfavorable conditions for the functioning of various human organs and systems.

In special medical manuals, the posture is defined as the habitual posture of a person without restraint without active muscle tension.

Morphologically, the posture is defined as the habitual posture of a person who is unconstrained, which he accepts without undue muscular tension. From the point of view of physiology, posture is a skill or system of certain motor reflexes, which ensures in statics and dynamics the correct position of the body in space. In biomechanics, posture is considered as a relaxed posture of the body of a person in an orthograde position, estimated with consideration for the geometry of the body mass of a person.

In the vertical position, the head is held by the extensors of the head against the moment of its gravity. Due to cervical lordosis, the mass of the head is directed to the bending of the cervical spine, while the neck muscles also hold the work. Holding the head, with some lowering it forward, reflexively promotes an increase in the thoracic kyphosis. Holding the head with a slight bending of the cervical spine helps reduce the thoracic kyphosis.

Posture can be assessed by the geometry of the body mass of a person, since one of the reasons for its violation is the occurrence of an excessively large tipping moment with respect to one or two planes of space occupied by the human body. This causes excessive strain of the extensor muscles and deformation of the longitudinal axis of the spinal column.

The term "mass geometry" was proposed by the Frenchman Anton de la Guupier in 1857. At present, the mass geometry of the body characterizes the distribution of the body's biotic links in space with respect to the somatic reference system, includes data on the location of the common center of mass, the moments of inertia of the biovarions relative to their axes and planes of rotation, ellipsoids of inertia and a number of other indicators.

With varying degrees of rigor, reliability and objectivity, the geometry of the body's mass has been studied by many authors for a long time.

The desire to study and reveal regularities in the size of the human body arose in ancient times in Egypt, intensified in the heyday of Greek classical art and achieved the greatest results in the Renaissance.

At various times, many systems for calculating the sizes and proportions of the body-the so-called canons-have been proposed. When using the canon for a measure unit, the length of any particular part of the body (module) was usually taken. Using this unit of measurements, through it you can express the size of each part of the body, assuming that on average it is a multiple of the dimensions of this module.

The height of the head, the length of the middle finger of the hand, and the length of the spinal column were suggested as a module.

Even the ancient Egyptians believed that the length of the middle finger of the hand fits in the length of the whole body 19 times.

The first of the known canons was created in the 5th century. BC. A polyclute. As a module, he took the width of the palm at the level of the root of the fingers.

In the Renaissance introduced a lot of new in the doctrine of the proportions of the human body of Leonardo da Vinci. For the module, he took the height of the head, which folded 8 times in the growth of the human body.

We know almost nothing about the proportions of the human body established by Michelangelo. However, it is known that he was constantly studying the proportions of the human body, as indicated by his drawings and sketches.

Colman proposed a canon in which the human body was divided into 100 equal parts. With this decimal proportions system, the dimensions of individual parts of the body could be expressed as a percentage of the total growth. Thus, the head height was 13%, the length of the trunk - 52-53%, the length of the leg - 47% and the arms - 44% of the length of the entire body.

Most of the canons proposed at a later time were built on a different principle. For the module, the most constant part of the skeleton was taken - the vertebral column, not all of it, but 1/4 part of it (the canon of Fritsch-Stratz).

Of great interest are the studies of the proportions of Karuzin (1921). At the heart of the canon created by him lies the geometric construction of the figure by Fritsch-Stratz. Complementing the proportions of the lower limbs, Karuzin introduced into the system their measurements and the size of the length of the foot, and also outlined the width of the pelvis (interverted diameter). When taking into account the size of the upper limbs, the author added shoulder width.

To determine the relationship between the linear dimensions of the segments of the human body and its growth, a "pars" value equal to 1/56 of a person's growth was introduced.

As you know, the proportions of a living body are very variable, in particular, they depend on the type of physique. At present, there are more than one hundred classifications of the human constitution based on various signs. Therefore, there are constitutional schemes based on morphological, physiological, neuropsychiatric and other criteria. Attempts to divide people into types according to their constitution were undertaken in practical anthropology for as long as anthropology itself exists.

Still Hippocrates (460-377 BC.) Distinguished the constitution as bad and good, strong and weak, dry and moist, elastic and sluggish. In ancient Indian medicine there are such typological characteristics of people as "gazelle", "deer", "elephant-like cow", etc.

Later, Galen developed the concept of habitus, referring to the set of morphological features that characterize the appearance of a person.

In 1914, Mr .. Siego proposed to determine the constitution of man on four basic systems of organs - digestive, respiratory, muscular and nervous. Depending on which system prevails, the author singled out four types of the human constitution: respiratory (respiratory), digestive (digestive), muscular (muscular) and cerebral (cerebral).

In the respiratory type, all airways and airways are well developed, they have a long thorax, a small stomach, an increase above the average.

Representatives of the digestive type have a large belly, conical, dilated downward chest shape, obtuse subhorbid angle, low growth, strongly developed lower part of the head. They have developed departments connected with the digestive organs. The high position of the diaphragm determines the horizontal position of the heart.

• For muscular type characterized by well-developed musculoskeletal system. The thorax in people of this type is cylindrical, wider than in people of the respiratory type.
• The cerebral type is characterized by the development of the cerebral cranium. The constitution is slender, podkrudinny angle acute.

Shevkunenko and Gesilevich (1926), on the basis of the ratio of the forms of individual parts of the body, distinguished three types of the human constitution:

• Dolichomorfny type - distinguish the longitudinal dimensions of the body, height above the middle, a long and narrow chest, narrow shoulders, long limbs, short trunk.
• The brachymorph type is squat, broad, with well-defined transverse dimensions, a long trunk, short extremities, neck and chest.
• Mesomorphic type - characterized by intermediate signs (between dolichomorphic and brachymorphic types).

The German psychiatrist Kretschmer (1930) singled out the types of the human constitution that are close to the classification of Sego by morphological features. He distinguished three types: picnic (Digestive type according to Sego), asthenic (cerebral) and athletic (muscular). Kretschmer suggested that by these categories one can classify all people as predisposing to a certain mental illness.

Chernorutskii (1927), on the basis of a study of the location of organs, their shape, metabolic peculiarities, proposed to distinguish three types of constitution: asthenic, normostenic and hypersthenic. In determining the constitutional types, the author used the Pignier index:

I = L - (P + T),

Where I is the dimensionless index; L is the length of the body, cm; P - body weight, kg; T - chest girth, see This scheme was widely used in medical practice.

In astenikov usually more long light, small heart, low blood pressure, high metabolism, enhanced function of the pituitary, thyroid and gonads, decreased function of the adrenal glands, the tendency to shift bodies down.

For hypersthenics characterized by high standing of the diaphragm, the horizontal position of the heart, a short but ample light, hypersecretion of the adrenal gland, high blood pressure, high blood levels of hemoglobin and red blood cells.

In normostenics, all indices fluctuate within the limits of average values. On the basis of the development of connective tissue (histological principle) Bogomolets (1928) distinguished four types of the human constitution:

• The asthenic type is characterized by the development of a predominantly loose connective tissue, which is capable of high reactivity and resistance.
• Fibrous type - large development of dense fibrous connective tissue.
• The pasty type is a loose "raw", "swollen" connective tissue, prone to fluid retention.
• Lipomatous type - strongly developed fatty tissue. All the examined constitutional schemes were applied mainly to men.

Shkerli (1938) developed a classification of constitutional types for women on the basis of the number and nature of fat deposition. He identified two main types with subtypes:

I type - with a uniform distribution of the subcutaneous fat layer:

• normally developed,
• Strongly developed,
• poorly developed fat layer.

II type - with uneven fat content:

• in the upper half of the body - the upper subtype,
• in the lower half of the body - the lower subtype.

Fatty deposits can be localized either in the trunk region (usually in the areas of the mammary glands or on the stomach), or in the gluteal region and in the region of the large trochanter.

A somewhat different classification of the constructional types for women was proposed by Talent. It is based on both morphological features and psychophysical differences. The author proposed to allocate 7 constitutions, combining them into three groups.

I group: leptosomal constitutions with a tendency to grow in length.

• The asthenic type is characterized by a thin physique, long limbs, a narrow pelvis, a belly drawn, a weakly developed musculature, a narrow long face.
• The stenoplastic type is narrow-cut, possessing a good general fatness, a moderate development of all tissues, approaching the ideal of female beauty.

Group II: mesosome constitutions with a tendency to grow in width.

• The picnic type is characterized by relatively shortened limbs, a round head and a face, a broad pelvis with characteristic fat deposition, relatively broad and rounded shoulders.
• Mesoplastic type differs squat, stocky figure, broad face, moderately developed musculature.

III group: megalosomal constitutions - the same growth in length and width.

• Euryplastic type - "type of fat athletics". This type is characterized by a strong development of fat with pronounced features of the athletic type in the structure of the skeleton and musculature.
• Subatellite t and n, or a real feminine type of constitution in the athletic structure of the body. They are tall, slender women of strong build with moderate development of muscles and fat. For the athletic type is characterized by an exceptionally strong development of the musculature and skeleton, a weak development of fat, a narrow pelvis, male facial features.

In 1929, Stefko and Ostrovsky proposed a scheme of constitutional diagnosis for children. The basis of this constitutional scheme is the fat release, the degree of development of the muscles and the shape of the chest. The scheme is applicable for both boys and girls. The authors identified five normal types: asthenoid, digestive, thoracic, muscular, abdominal and, in addition, mixed types: asthenoid-thoracic, muscular-digestive, etc.

• The asthenoid type is characterized by a thin and delicate bone structure. Predominantly developed lower limbs, thin tapering down the thorax, acute podkridinny angle, the stomach is poorly developed.
• Digestive (digestive) type is characterized by a strongly developed abdomen, which, protruding, forms folds over the pubic surface. Podkrudinny corner is blunt.
• The thoracic (thoracic) type is characterized by a strong development of the thorax (mainly in length) with simultaneous development of those parts of the face that take part in breathing. The thorax is long, the podkrudin angle is sharp, the abdomen is relatively small, in shape resembling a pear facing downwards, the vital capacity of the lungs is large.
• The muscular type is characterized by a uniformly developed trunk. The thorax is of medium length, the podkrudinny angle is medium, the shoulders are high and wide, the abdomen has the shape of a pear facing the bottom. Strongly developed muscles, especially on the limbs. Body fat is negligible.
• Abdominal (abdominal) type is a special modification of the digestive type. It is characterized by a significant development of the abdomen with a small chest, not a strongly developed fat layer, a significant development of all parts of the large intestine.

The research conducted by Davydov (1994) made it possible to reveal the age-specific features of the distribution of children of preschool and primary school age by constitutional types.

The data obtained by the author indicate that during the physical activity there are significant changes in the morphological and functional order, while the nature of their influence is ambiguous for different systems of the organism and is not the same in different periods of ontogeny. The author has isolated conservative (rhythm of development, linear dimensional features, histological characteristics) and labile (functional systems, body weight) components of the morphology and functions of the human body in relation to the effects of physical exercises. On the basis of the obtained data, the permissible possibility of using physical load as a regulator and stimulator of morphofunctional development in human ontogenesis was determined.

It should be noted that there is no single approach to the definition of a human constitution. This applies both to the definition of the very concept of "the constitution of a person", and to constitutional diagnostics - a characteristic of constitutional types. In the literature, most specialists tend to use the term "somatotype" to characterize the constitution.

At present, among the many schemes of normal constitutions, researchers usually distinguish three constitutional types of physique:

• picnic endomorphic type - convex thorax, soft rounded forms due to the development of the subcutaneous base, relatively short limbs, short and wide bones and feet, large liver;
• athletic mesomorphic type - trapezoid shape of the trunk, narrow pelvis, powerful shoulder girdle, well developed musculature, rough structure of bones;
• asthenic ectomorphic type - flat and long thorax, relatively wide pelvis, lean body and weak development of subcutaneous base, long thin limbs, narrow feet and brushes, minimal amount of subcutaneous fat.

Naturally, the constitutional characteristics of most individuals could not be reduced to these three types. This division gives only a general idea of the range of fluctuations in the constitution of a person. Therefore, for example, in the practice of sports selection, we focus not on the extreme types, but on the continuously distributed components of the physique, which can be distinguished by three: endomorphic, mesomorphic and ectomorphic. The degree of expression of components is different for different individuals and can be estimated from the seven-point system (7-1). The highest score of the component corresponds to the highest score (7). The description of the somatic type is made in three digits. For example, the somatotype, expressed in figures 7-1-1, has a rounded shape, a strong development of the subcutaneous base, a weak musculature, large interiors (picnic type) with a weak degree of mesomorphic and ectomorphic components (mesomorphia indicates athletic, and ectomorphy-asthenic physique). Extreme variants of type 1-7-1, 2-1-7 are rare, the most common somatotypes are 3-5-2, 4-3-3, 3-4-4. It should be noted the interdependence of all three components: increasing one leads to a decrease in others. Therefore, the high values of one component practically exclude the high values of the other two. When evaluating a somatotype, the sum of the three estimates should not exceed 12 and can not be less than 9 points.

[1], [2], [3], [4], [5], [6]