Dr. Med., Professor A.L. Pokhachevskiy^{1, 2}
O.V. Graph³
PhD, Associate Professor A.B. Petrov^{3, 4}
V.S. Akulin²
L.K. Grigoryan^2
1I.M. Sechenov First Moscow State Medical University, Moscow
²I.P. Pavlov Ryazan State Medical University, Ryazan
³Lesgaft National State University of Physical Education, Sports and Health, St. Petersburg
⁴V.A. Almazov National Medical Research Center of the Ministry of Health of the Russian Federation,St. Petersburg

Keywords: neurohumoral regulation, vertebral artery, polyathlete athletes.

Introduction and rationale. In general the functional state (FS) of the organism is determined by its neurohumoral regulation [1–3]. The latter is determined by the viability of the blood supply to the brain. Despite the fact that the vertebral arteries provide 25% of its demand (the rest falls on the internal carotid artery), the brain stem, which is responsible for maintaining life support functions, is supplied exclusively from this pool. The insufficiency of the vertebrobasilar circulation is associated with a change in the cross section, volumetric and linear blood flow velocity of the vertebral arteries. Since these arteries pass through the transverse processes of the cervical vertebrae, the orientation and relative position of the latter will have a direct impact on their consistency. A change in the mobility of the cervical spine, expressed in a decrease and asymmetry of the angles of inclination and rotation of the head relative to physiological axes, caused by a violation of the tone of the deep muscles of the neck, is probably the cause of circulatory disorders along the vertebral arteries. The latter circumstance will probably be manifested by a violation of neurohumoral regulation and FS depression. In turn, the restoration of mobility of the cervical spine is likely to lead to an improvement in neurohumoral regulation and the functional state of the athlete's body. Objective. To find out the connection between the restoration of blood circulation in the basin of the vertebral artery and the improvement of the functional state of the athlete's body. Materials and methods. A focus group of active athletes, polyathletes, track and field athletes (12 people, 17-22 years old), MS qualification, CMS, 1 sports category was studied. The study included, firstly, an assessment of the mobility of the cervical spine in the sagittal, frontal and vertical axes. Secondly, in case of identified mobility disorders, an ultrasound scan of the brachiocephalic vessels (US) was performed, the diameter and linear velocity of the blood flow of the vertebral arteries were assessed in areas V1 (from the beginning to the transverse process of the 6th cervical vertebra (C-6)), 2 (from C-6 to C-2), 3 (from C2 to the entrance to the spinal canal C1) on the left and right. Thirdly, after identifying mobility disorders and their objective confirmation by ultrasound, each athlete underwent up to 3 sessions of individual myo-correction, including acupressure, reflex, vacuum massage of the cervical region. Fourthly, an active orthostatic test (AOT), during which the electrocardiogram was recorded for 5 minutes in the supine position (clinostasis), and then standing (orthostasis), including an active transition from clinostasis to orthostasis. The current functional state (FS) was assessed by the TP indicator (total power of the spectrum), taking into account the contribution of fast oscillations (HF-component) - reflecting the activity of the parasympathetic division of the autonomic nervous system, slow oscillations (LF-component) - a marker of the activity of sympathetic influences and very slow fluctuations (VLF-component) – reflecting humoral-metabolic and cerebral ergotropic influences on HR. The LF/HF ratio was regarded as sympathetic reactivity. The reactivity of the parasympathetic division was assessed by a ratio of 30:15 [1]. Fifth, ultrasonic scanning of blood vessels and assessment of FS by the frequency spectrum of HR during AOT were carried out twice: during the initial detection of cervical mobility disorders and after myo-correction. The results of the study were processed using the statistical package Statistica 10.0. Results. In all cases of changes in the mobility of the cervical spine, ultrasound scanning confirmed various degrees of disturbance and asymmetry of blood circulation in the basin of the vertebral artery. At the same time, a decrease in the diameter of the vertebral artery revealed in V1, 2, 3 areas corresponded to a decrease in the linear and volumetric blood flow velocity in them. The asymmetry of the blood supply during the initial examination is manifested by a low level of the total power of the spectrum, based on which, in fact, there are no fast elements of regulation. At the same time, the basis of regulation is humoral-metabolic waves both in ortho- and clinostasis. After individual myo-correction, partial restoration of blood circulation was confirmed by repeated ultrasound scanning. The frequency analysis revealed an increase in the total power of the spectrum and its redistribution to the high-frequency region. In clinostasis, the role of rapid regulation increases, which already makes up 2/3 of the entire spectrum; in orthostasis, despite the predominance of humoral-metabolic activity, the sympathetic component occupies a third of the total power, and together with parasympathetic activity, it makes up 44.5%. The Ewing index increases significantly (from 1.15 to 1.35), which also indicates an increase in parasympathetic reactivity. Conclusions. Thus, the identified chain of relationships proves the connection between the restoration of blood circulation in the basin of the vertebral artery and the improvement of the functional state of the athlete's body: a change in the tone of the deep muscles of the neck, leading to displacements of the cervical vertebrae, causes a violation of blood circulation in the basin of the vertebral artery. The latter circumstance is the cause of insufficient blood supply to the autonomic centers of the brain stem, which leads to a violation of neurohumoral regulation. In turn, the restoration of the musculoskeletal relationships of the cervical spine contributes to the restoration of the blood supply to the vegetative centers and, as a result, to the improvement of the athlete's body's FS.

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