Dr.Biol., Professor N.I. Shlyk¹
Master of Sports Physiology E.S. Lebedev²
Master of Sports Physiology O.S. Vershinina^2
1Udmurt State University, Izhevsk
²Udmurt Republican Team Training Center, Izhevsk

Keywords: training process, cross-country skiers, biathletes, autonomic regulation, heart rate variability, typological features, overtraining risks, arrhythmia.

Background. Efficient training systems customizable to the individual autonomic regulation types are known to improve the adaptation processes, particularly in the cardiovascular system. The adaptability excelling process directly depends on the individual autonomic regulation and autonomic reactivity types [4-6], with the necessary comprehensive autonomic regulation test rates obtainable on a daily basis by the autonomic vascular regulation (AVR) express tests.

Objective of the study was to analyze benefits of the daily HR variation tests with account of the individual autonomic vascular regulation types – for the early overtraining detection and competitive performance forecasting purposes in the modern cross-country skiing and biathlon.

Methods and structure of the study. The autonomic vascular regulation rating studies were run by the Udmurt State University team composed of master physiologists at the Udmurt Republican Team Training Center and the cross-country skiing and biathlon facilities of the latter. Subject to the study were the 15-24 years old cross-country skiers (n=54) and biathletes (ranked Class I to MS) from the Udmurt Republican Teams. Every athlete was tested for autonomic vascular regulation prior to each training session by Varicard 2.51 computerized test system (5min in recumbent and 6min in standing position) with the test data processed by Varicard MP software – that makes it possible to fix and process test data of four athletes at a time. The whole team was tested for 30min to provide the coaches with comprehensive data on the each teammate functionality, adaptation reserve and rehabilitation progress to have the training process efficiently customized to the individual fitness and functionality. On the whole, 2500 autonomic vascular regulation tests were made for the study purposes.

The autonomic vascular regulation test data were grouped and analyzed by the individual autonomic regulation types determined using the N.I. Shlyk classifier [4] as follows: moderate central autonomic vascular regulation (type I) with SI>100 conv. units and VLF>240 ms²; expressed central autonomic vascular regulation (type II) with SI>100 conv. units and VLF<240 ms²; moderate autonomic vascular regulation (type III) with SI = 30-100 conv. units and VLF>240 ms²; and expressed autonomic vascular regulation (type IV) with SI = 10-30 conv. units, VLF>240 ms² and ТР>8000 ms².

When the autonomic vascular regulation test data show a sharp decline with SI<10 conv. units associated with a rapid growth of TP>16000-20000 ms², it should be interpreted as indicative of the sinus node functionality disorders manifested by arrhythmia on the cardiointervalogram, autonomic vascular regulation scattergram and ECG. Every other temporal and spectral autonomic vascular regulation test rate must be fixed as well. Most favorable are the moderate autonomic (type III) and moderate central (type I) autonomic vascular regulation types. It should be emphasized that the expressed autonomic vascular regulation (type IV) may be either normal for elite athletes or pathological i.e. associated with an overtraining and/ or high risk of a health disorder. In the latter case, the quiescent-state autonomic vascular regulation rates are found to grow, with the only exclusion for SI, with some changes in the cadiointervalogram, autonomic vascular regulation scattergram and ECG. 

Orthostatic tests are obligatory as they make it possible to profile in more detail the autonomic reactivity and reserve capacities. Hyper/ hypo/ paradoxical reactions to the orthostatic tests may be indicative of the sagged adaptation reserves due to overtraining or a health disorder. When the autonomic reactivity in orthostatic tests is normal, every autonomic vascular regulation test rate (МхDMn, TP, HF, LF, VLF, ULF) tend to drop, with the only exclusion for SI. Due consideration in the autonomic vascular regulation test data analyzing process should be given to the actual training workloads versus the prior ones (the day before) and the individual complaints of the athletes, particularly sleeping disorders and other health dysfunctions [1, 2, 3, 7].

Results and discussion. The autonomic vascular regulation test data and analyses found serious pitfalls in the skiers’ and biathletes’ training systems. Generally, the one-for-all blanket training workloads (non-customized to the individual autonomic vascular regulation types) were found to expose some athletes to overtraining, particularly those with the relatively low reserve capacities. The overtraining effects were found associated with the regulator system realignments detectable by the pathological functionality profiles of the cardiac function control systems.

Furthermore, we found the training workloads non-customized to the individual autonomic vascular regulation types being associated with the high risks of autonomic imbalances in the first and latter training microcycles, particularly in transition to altitude trainings. Further trainings of the athletes with health disorders were found to mobilize the still untapped bodily resources with further aggravation of the autonomic regulation. Furthermore, in cases of transfers of athletes from one coaching team to another, the new coaches were found negligent of the prior training systems, experiences and workloads, and the revisions were tested to further aggravate the autonomic regulation, adaptability and resources in the precompetitive trainings at special detriment to the competitive performance. It was also found that excessive training workloads in combination with sauna may be detrimental to rehabilitation processes in the young athletes. The study data showed a close correlation between functionalities of the cardiac performance control systems and competitive success rates.

Conclusion. The study shows benefits of the daily autonomic vascular regulation tests that help effectively customize the training workloads to the individual autonomic vascular regulation types and autonomic HR regulation. The study found the autonomic balance realignment mechanisms in skiers and biathletes in every training process stage and recommended the most informative quiescent-state and orthostatic autonomic vascular regulation test rates. The study findings may be beneficial both for the theoretical and practical purposes. First, knowledge of the individual autonomic vascular regulation type helps the coach to forecast the individual adaptive responses in the training process. Second, the autonomic vascular regulation express tests give highly valuable data for detection of overtraining symptoms in the early stages to make necessary corrections to the training system.

The study data demonstrates once again that the individual adaptation reserves may be very different and, hence, blanket training workloads may be detrimental to athletes of certain autonomic vascular regulation types. High competitive accomplishments are possible only when the training system is sensitive to potential deregulations to secure prudent mobilization of the individual adaptation reserves and good cardiac performance controls. It should be emphasized that only a well-balanced regulation makes it possible to fully mobilize the individual functional and reserve capacities in the regular and altitude trainings.

It was further found that when coaches are negligent to the individual regulatory and reserve capacities and fail to customize the training systems to the latter (i.e. offer indiscriminant training schemes to skiers and biathletes of different autonomic vascular regulation types), with the training process customized only to the HR data without autonomic vascular regulation express tests, and with the situation further aggravated by a poorly controlled rehabilitation service – such trainings often expose the athletes to fatigue, overtraining, chronic physical stresses on the whole and stresses on the cardiovascular system in particular.

As reported by the global sport health statistics, athletes often die of hearth failures, and this is the reason why the athletes with serious disorders in autonomic homeostasis (with autonomic vascular regulation test data indicative of domination of central/ autonomic regulation, showing paradoxical orthostatic test results and changes in the cardiointervalogram, autonomic vascular regulation scattergram and ECG) shall not be qualified for competitions – for they are in need of special medical examinations, tests, rehabilitation service and customized trainings.

Therefore, we recommend the modern training systems being designed collectively by scientists, coaches and sport physiologists with daily autonomic vascular regulation tests and with due consideration to the individual autonomic vascular regulation types. Such tests and analysis may be indispensable for the sport reserve training systems and elite sports to secure high competitive accomplishments and good health service.

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 during stress]. Moscow: Nauka publ., 1984, pp. 200- 221.
2. Gavrilova E.A. Ritmokardiografiya v sporte [Ritmocardiography in sports]. St. Petersburg: SZGMU publ., 2014, 164 p.
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6. Shlyk N.I. Ekspress-otsenka funktsionalnoy gotovnosti organizma sportsmenov k trenirovochnoy i sorevnovatelnoy deyatelnosti (po dannym analiza variabelnosti serdechnogo ritma [Express assessment of athletes' functional fitness for training and competitive activities (based on HRV data]. Nauka i sport: sovremennye tendentsii, 2015, v. 9.no.  4. pp. 5-15.
7. Shlyik 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 activities of athletes (case study of skiing sports]. Lechebnaya fizicheskaya kultura i sportivnaya meditsina. 2016. no. 1 (133). pp. 17-23.

Corresponding author: medbio@uni.udm.ru

Abstract

The study analyzes some aspects of the practical experience accumulated by a new experimental project to rate the training workloads versus the individual HR variations and autonomic regulation of heart rate, with elite cross-country skiers and biathletes from Udmurt Republican teams sampled for the study. The tests were dominated by daily express tests of the HR variations, with the test data and analyses used to design a new method to rate the exposure to overtraining risks and potential health disorders and prevent the training workloads coming in conflict with the cardiac performance control systems. A special priority in the HRV analyses was given to the individual autonomic regulation test data. The daily HRV express tests made it possible to map out the individual autonomic regulation features, and the body rehabilitation potentials to provide guiding frames for the individual training system design, management and competitive performance forecast purposes. The individual HRG profiles helped us detect serious irregularities in the skiers’ and biathletes’ training policies and practices. It was found, among other things, that the standard non-individualized training workloads insensitive to the autonomic regulation types expose the athletes to overtraining risks that are particularly high for the ones tested with low reserve capacities. It was further found that overtraining result in negative adjustments of the reactive mechanisms and stable pathologies in the cardiac performance control systems. The study also found that the training systems were customized neither to the individual autonomic regulation types nor to the altitude training cycles, and this negligence has often resulted in the autonomic regulation imbalances in early stages (first and the following micro-cycles) of the training process. Further trainings of the athletes with health disorders were found to mobilize the still untapped bodily resources with further aggravation of the autonomic regulation. Furthermore, in cases of transfers of athletes from one coaching team to another, the new coaches were found negligent of the prior training systems, experiences and workloads, and the revisions were tested to further aggravate the autonomic regulation, adaptability and resources in the precompetitive trainings at special detriment to the competitive performance. It was also found that excessive training workloads in combination with sauna may be detrimental to rehabilitation processes in the young athletes. The study data showed a close correlation between functionalities of the cardiac performance control systems and competitive success rates.