HEART RATE VARIABILITY IN HIGHLY SKILLED ORIENTEERING ATHLETES WHEN SOLVING COMPLEX MOTOR TASKS

Currently, the problem of improving the quality of the training process in both professional and novice athletes is a priority for experts in the medical and biological support of sports all over the world. For these purposes, various biofeedback procedures, including the method of solving specialized motor-cognitive tasks on the stabilometric platform [1], have been actively used in recent years as extra-training means to improve sports performance. At the same time, we should note that one of the most informative biological signals that allow to judge about the change in the functional state of the body of the tested athletes in the process of sports training is the dynamics of heart rate variability (HRV) [2]. HRV analysis is widely used as a non-invasive and reliable tool for assessment of vegetative control of human cardiovascular system [3]. Numerous literature sources confirm the prospect of using this method for the purposes of sports physiology [4] However, changes in HRV in highly qualified athletes when solving complex motor and cognitive tasks, as of today, still remain unstudied. The aim of the present study was to assess changes in heart rate variability in highly qualified orienteering athletes when solving complex coordination tasks on biocontrol of a virtual object using a stabilometric platform ST-150. Seven days training with biofeedback control on the stabilometric platform resulted in a significant increase of such HRV temporal indices as SDNN – by 8,9 % (p<0,01), RMSSD – by 42,3 % (p<0,05), pNN50 – by 77, 1 % (p<0.05), CV – by 25.3 % (p<0.01), as well as heart rate reduction by 10.5 % (p<0.05), which indicates an increase in functional capabilities of the athletes’ bodies, strengthening vagus effects on cardiac rhythm. The results of geometrical analysis have shown that biofeedback according to reference reaction leads to reliable increase of values of index of mode of cardiointervals by 9,7 % and increase of variation range of histogram of cardiointervals by 21,4 % as well as decrease of values of mode amplitude by 19,2 % and tension index of regulatory systems of the body by 29,6 % (p<0,05), which testifies to improvement of adaptation possibilities of the body of tested sportsmen under the influence of this type of biocontrol. Analysis of spectral components of heart rhythm in orientation athletes after 7-day training with biofeedback control has shown significant increase in TP by 36 %, LF – by 37,7 %, HF – by 88,2 % as well as decrease in LF/HF by 28,2 % (p<0,05), which testify to increase in general variability of heart rhythm, activation of parasympathetic regulation circuit, increase in functional capabilities and reserves of tested athletes organism.