Assistant P.A. Kulagin¹
Associate Professor S.V. Stroilov²
PhD, Associate Professor G.M. Lavrukhina³
PhD, Associate Professor N.N. Aksenova³
A.K. Konstantinova^3
1I.P. Pavlov Ryazan State Medical University, Ryazan
²The Academy of the FPS of Russia, Ryazan
³Lesgaft National State University of Physical Education, Sports and Health, St. Petersburg

Introduction. The identification of markers of the directional dynamics of the functional state of the body in the chosen sports specialization allows us to objectively judge the individual adaptive capabilities of an athlete and probabilistically predict competitive success.
The aim of the study is to detect markers of the directional dynamics of the functional state of the body of shooters in the process of sports training.
Methodology and organization of the study. A group of active shooting athletes (12 people) aged 17-22, MS qualification, CMS was examined during the preparatory and competitive periods. FS was assessed based on the frequency characteristics of heart rate variability (HRV) during an active clinoorthostatic test (AOP). Registration and analysis of HRV indicators were carried out in accordance with the International Standard (1996).
The results of the study and their discussion. During the competitive period, the total power of the spectrum remains at the average population level (3500 ms2), its insignificant growth (by 20%) occurs solely due to parasympathetic activity, while both the humoral-metabolic (to a greater extent) and the sympathetic component decrease (by a third). Accordingly, the vegetative balance index (LF/HF) decreases (by half) statistically significantly. Despite the lack of statistical significance of the growth of adaptive reserves, the quality of their distribution changes significantly: two thirds are fast – parasympathetic activity, one third for sympathetic and humoral–metabolic effects, while at the beginning of the season: half of the reserves are for parasympathetic activity and a quarter for slower participants.
During the competitive period, the basis for adaptation differences is not only an increase by a third of the total power of the orthostasis spectrum to 2200 ms2, but also a decrease in clinoorthostatic variability from 1700 to 1100 ms2, which significantly increases adaptive reserves, not only due to their direct growth, but also a decrease (including qualitative) in the physiological cost of clinoorthostatic transition. If at the beginning of the season it manifested itself solely due to parasympathetic variability, then during the competitive period, parasympathetic participation increased by 1.8 times, sympathetic (actually absent) by 9.5 times.
The differences in the spectrum are also very significant: sympathetic activity increases twice up to 1400 ms, parasympathetic activity decreases by a quarter and humoral-metabolic activity increases by only 15%. The growth of the 30/15 index by 10% to 1.48 has no statistical significance, while sympathetic reactivity (LF/HF) increases significantly, more than twice, from 3.13 to 6.91.
Conclusions. The improvement in the quality of adaptive reserves during the competitive period is confirmed in clinostasis: by absolute growth and relative redistribution in favor of parasympathetic regulation; in orthostasis: by a qualitative decrease in the physiological cost of the clinoorthostatic transition, by a pronounced absolute increase and redistribution of sympathetic activity.

Keywords: heart rate, neurohumoral regulation.

References

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