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BIOMECHANICS OF BLOOD CIRCULATION OF TEENAGERS IN DIFFERENT MEDICAL GROUPS OF PHYSICAL EDUCATION

Relevance. The health of teenagers should be assessed not only by their morphometric data, but also by the functional state of the main organs and systems that provide adaptive reserve potential. 
Objective. The purpose of our study was to evaluate the functional capabilities of the cardiovascular system of teenagers according to biomechanical  indexes  of blood circulation. 
Methods and materials. 272 teenagers aged 13–14 (176 boys and 96 girls) participated in the study. Among the boys, there are 104 pupils of the basic medical group of physical education and 72 of the preparatory group (2nd health group). There were 48 primary and 48 preparatory group pupils among the girls. The results of Kubicek rheography and rheovasography were used to study the biomechanical parameters of the cardiovascular system. They were evaluated using the methods of mathematical statistics (the MedStat program (Ye. Lyakh, 2006)). 
Results. There were no any statistically significant differences between most of the rheovasographic parameters of the students of the preparatory and basic medical groups of physical education. Instead, there are certain distinctive features of the peripheral blood flow of pupils of the preparatory group of physical education (with reduced functional capabilities). Thus, the , indexes of the rapid filling timing in the pupils of the preparatory group of physical education are lower than in the main group.In the boys of the preparatory group of physical education on both hands and in the girls of this group on the left hand, the blood flow time for the forearms is slightly increased. Greater deviations from the norm for the amplitude of rheograms were found in pupils of the preparatory group of physical education. 
The number of pupils with asymmetric blood supply to the forearms in the preparatory group of physical education is more than in the main group. A decrease in the blood supply of the vessels of the forearms is registered more often in teenagers who are assigned to the preparatory group of physical education. In the boys of the preparatory group of physical education, the blood vessels of the shins are worse. 
Conclusions. Some distinctive features for the state of peripheral blood flow of teenagers in the preparatory group of physical education were revealed. Thus, the indexes of the rapid filling timing, the amplitude of the rheograms were lower, and the time of propagation of the pulse wave was higher than normal. Asymmetry and decreased blood flow in the vessels of the upper and lower extremities were noted in most teenagers with impaired