Man's height
An increase in the size of the body as a whole or its individual tissues and organs; in a narrower sense, the length of the human body. Growth (development) is a general biological property of living matter and is most characteristic of a young organism.
There are progressive, stable and regressive stages of growth. The progressive stage covers the prenatal period and the period after birth until approximately 20 years. In women, growth continues until 16-18 years, in men up to 18-20 years.
Subsequently, there is a relative stabilization of growth, and starting from the age of 50, a slow decrease (approximately 1 cm every 10 years). The greatest increase in growth is observed in the first years of life, then its speed slows down and again sharply increases during the period of maturation (see Infant, Preschool age, Adolescence, School age, Toddler age). The decrease in R. h. in old age is explained mainly due to the shortening of the spine due to its curvature, as well as due to a decrease in the elasticity of the intervertebral discs and their flattening.
However, at any age, R. changes throughout the day: in the evening the growth is always slightly less than in the morning. This is explained by the fact that during the day the weight of the body puts pressure on the spine and the intervertebral discs become somewhat flattened. At night, when a person lies down, the spine is freed from heaviness, the intervertebral discs, due to their elasticity, straighten and by morning the spine is restored. This difference in R. does not exceed 1-1.5 cm. However, in some cases (with heavy muscular work, especially lifting and carrying heavy objects) it can reach 3-4 cm or more.
In all countries, for many decades, the average size of R. was taken to be 165 cm for men and 154 cm for women. However, this value may vary somewhat among individual nationalities. For example, the average height of residents of Scandinavian countries is 10-15 cm greater than that of residents of Italy or France. In recent years, due to the phenomenon of the so-called. acceleration, the average value of R. increased to 167-168 cm for men and 156-157 cm for women.
Many theories have been proposed to explain the causes of acceleration, but none of them are able to explain this complex biological phenomenon. process. The main reason for acceleration is considered to be a change in the quality of nutrition, greater consumption of proteins and fats. The widespread increase in R. during the 19th and early 20th centuries. suggests that, most likely, acceleration is associated with a whole complex of various factors involved in stimulating the growth and development of the body (increasing living standards, improving nutrition, reducing morbidity, etc.).
R. is greatly influenced by the so-called. growth hormone produced by the pituitary gland and stimulates the growth of a young body. This hormone increases protein synthesis and also retains phosphorus, calcium and sodium salts in the body, which are necessary for building bones and other tissues. The hormone is secreted throughout life and plays a very important role in regulating growth processes. The lack of this hormone in childhood leads to a sharp retardation of growth, so-called dwarfism; with its excess production, gigantism is observed, in which a person’s height can reach 240-250 cm. In an adult, with increased production of the hormone, the size of the fingers, toes, and hands increases and feet, nose and lower jaw (see Acromegaly).