PhD, Associate Professor I.S. Tamozhnikova¹
PhD, Associate Professor M.M. Bogomolova¹
PhD, Associate Professor N.A. Kuropatkina¹
S.A. Kormilin^2
1Volgograd State Academy of Physical Culture, Volgograd
²Plekhanov Russian University of Economics, Volgograd

Keywords: physical activity, control of the parameters of the cardiovascular system.

Introduction. The training process to a certain extent affects the level of tension of the regulatory systems of the body. Irrational physical activity often leads to a breakdown of adaptation mechanisms, which, in turn, can negatively affect the state of health and physical activity [2]. The circulatory system is one of the leading systems in ensuring the body's adaptation to changing environmental conditions, physical and educational loads, and various stressful situations [1]. Timely monitoring of the parameters of the cardiovascular system by analyzing the heart rate variability makes it possible to obtain information about the degree of tension of the regulatory systems and the adaptive capabilities of the body [1].
The aim of the study is to conduct a comparative analysis of the adaptive capabilities of the body of athletes, depending on the level of physical activity.
Methodology and organization of the study. The assessment of the adaptive capabilities of the athletes ' body was carried out using the study of heart rate variability. The study involved 88 people (48 women and 40 men) aged 18-22 years, all of them were active athletes, had the categories of CMC or MS. The study was conducted in 2 stages, the 1st stage was completed in November 2019, the 2nd stage in connection with the Covid-19 pandemic was conducted in June 2020. In order to assess the level of physical activity of the subjects, we used the time-table method of determining the daily energy consumption. At the 1st stage of the study, the average daily energy consumption was 6,600 kcal, at the 2nd stage of the study, the level of physical activity of athletes significantly decreased due to the lack of training and averaged 2,300 kcal. In the process of interpreting the results of the study of heart rate variability, we followed the classification of functional states proposed by RM. Baevsky [1].
The results of the study and their discussion. As a result, at the 1st stage of the study, the state of the physiological norm was recorded in 25 % of cases, the prenosological state – in 48 % of cases, 20 % of the studied were assigned to the group of premorbid states and another 7 % - to the state of adaptation failure. At the 2nd stage of the study, the physiological norm was noted in 42% of students, the prenosological state-in 40 %, in 18% of premorbid states, there was no failure of adaptation.
Conclusion. The data obtained indicate that the level of physical activity has a significant impact on the functional state of the body. During the period of active training activity, athletes are more at risk of adaptation failure in comparison with the period of relatively low physical activity. Monitoring the parameters of the cardiovascular system can be used to optimize the level of physical activity.

Literature

1. Baevsky R. M. Analysis of heart rate variability using the "Varicard" complex and the problem of recognition of functional states / R. M. Baevsky, Yu. N. Semenov, A. G. Chernikova / / Chronobiological aspects of arterial hypertension in the practice of medical flight examination. - M., 2000. - pp. 167-178.
2. Platonov V. N. Peretrenirovannost v sporte / V. N. Platonov / / Nauka v olimpiyskom sporte. - 2015. - No. 1. - p. 19-34.