Dr. Biol., Professor N.I. Shlyk
Udmurt State University, Izhevsk

Objective of the study was to identify standards for the variation range of RR-intervals at rest and in orthostasis in training of racing skiers with different types of regulation
Methods and structure of the study. During the study, we conducted 559 dynamic HRV tests at rest and in orthostasis at different stages of the training cycle. Subject to the study were 34 racing skiers aged 17-22 years, having the sports qualifications of I adult category, CMS, and MS. The subjects were tested in the morning after the previous training day before the first training using the Varikard 2.51 hardware-software complex and Varikard MP program (Ryazan, Russia). The predominant type of autonomic regulation was defined by the classification proposed by N.I. Shlyk. Prior to each HRV test, the racing skiers were interviewed about the physical loads performed on the previous training day, their load tolerance, quality of sleep, well-being, and participation in competitions.
Results and conclusion. The study found that the predominant type of regulation at rest in each athlete defines the bounds of the MxDMn range, divisions of the autonomic nervous system, and level of the body’s functioning as a whole. 

Keywords: heart rate variability, variation range of RR-intervals, types of regulation, racing skiers, individual approach.

References

1. Bayevsky R.M., Kirillov O.I., Kletskin S.Z. Matematicheskiy analiz izmeneniy serdechnogo ritma pri stresse [Mathematical analysis of changes in heart rate under stress]. Moscow: Nauka publ., 1984. P. 200.
2. Shlyk N.I. Serdechny ritm i tip regulyatsii u detey, podrostkov i sportsmenov [Heart rate and type of regulation in children, adolescents and athletes]. Izhevsk: Udmurt University publ., 2009. 259 p.
3. Shlyk N.I., Gavrilova E.A. Analiz variabelnosti serdechnogo ritma v kontrole za trenirovochnoy i sorevnovatelnoy deyatelnostyu sportsmenov na primere lyzhnykh vidov sporta [Analysis of heart rate variability in control of training and competitive activity of athletes (case study of skiing sports)]. Lechebnaya fizicheskaya kultura i sportivnaya meditsina. 2016. No. 1 (133). pp. 17-23.
4. Shlyik N.I. Variabelnost serdechnogo ritma v pokoe i ortostaze pri raznykh diapazonakh znacheniy MxDMn u lyzhnits-gonshchits v trenirovochnom protsesse [Heart rate variability at rest and orthostasis for different ranges of MxDMn values for female skiers in training process]. Science and Sport: Current Trends, 2020, Volume 8, No. 1, pp. 83-96.