Dr.Biol., Professor Yu.V. Koryagina¹
PhD G.N. Ter-Akopov¹
PhD S.V. Nopin¹
PhD L.G. Roguleva^1
1North Caucasus Federal Research and Clinical Center of the Federal Medical Biological Agency, Essentuki

Key words: functional state, organism, men, middle and high mountains.

Introduction. The tract Jila-su (translated from Karachay-Balkar-warm water) is a resort area in Kabardino-Balkaria, 14 km North of mount Elbrus with a large number of thermal springs and waterfalls. The height above sea level is 2380 m. in the tract of Gila-su there is a tent camp, from which the ascent of Elbrus from the North begins.
The aim of the study is to identify the features of the functional state of the cardiovascular and respiratory systems of the human body in urgent adaptation to the conditions of the height of 2380 m in the tract jily-su in the Elbrus region.
Methodology and organization of the study. The work was attended by 10 young men 16-26 years old, permanently living in low mountains (550-650 m above sea level). The study of the cardiovascular and respiratory systems was carried out twice: 3 days before the trip to Essentuki (640 m above sea level) and during the first 2 hours of stay at an altitude of 2380 m (in the tract Gila-su). Indicators of cardiovascular and respiratory systems were studied: heart rate variability, Central hemodynamics, pulse oximetry, rheoencephalography and spirometry, circadian daily heart rate biorhythms.
The results of the study and their discussion. The results of the study show that during the period of urgent adaptation to height, young healthy men showed signs of hypobaric hypoxia [1, 2]: a decrease in blood saturation (up to 92.5±0.3 % compared to 96.5±0.3 %), palpitations and activation of the sympathetic nervous system tone (increased stress index and decreased SDNN), expansion of brain vessels (internal carotid artery basin - increased elastic modulus index on the left and right, decreased diastolic index on the left; vertebro-basilar basin - decreased indicators - left dicrotic index and peripheral resistance index, left and right-diastolic index), minor manifestations of high-altitude hyperventilation. All the studied parameters, except for venous outflow, were within the physiological norm. The two-fold excess of the physiological norm of the venous outflow index from the skull cavity is most likely not a consequence of the body's reaction to hypobaric hypoxia of the mountains, but, more likely, is caused by a forced prolonged sitting posture (more than 2 hours) when traveling in difficult road conditions to the destination – the tract of Jila-su. Disorders of circadian diurnal rhythms of heart rate have been identified.
Conclusion. Acute (urgent) adaptive effect of stay in the conditions of middle and high mountains does not cause significant stress of functional systems of the human body. It should be noted that young men took part in this study, and the presence of another contingent in these conditions requires further study and appropriate medical and biological support.

References

1. Modern technologies and effects of mountain and hypoxic training of athletes / Yu. V. Koryagina, G. N. Ter-Akopov, S. V. Nopin / / Resort medicine. - 2017. - No. 3.  Pp. 170-174.
2. Reps V. F. Technologies of increase of functional adaptation at athletes in the conditions of high-altitude hypoxia / V. F. reps, A.V. Grebenyuk / / Physiological journal. - 2012. - T. 58. - No. 4. – P. 78 - 84.