RESUMO
Application of the beta rhythm neurofeedback is mainly dealt with when considering issues related to improving attention for clinical or preventive purposes. Cognitive and autonomic interactions formed with the help of biofeedback training, changing the function of autonomic and visceral systems, qualitatively improve the efficiency of any activity, including athletic activity, the nature of which is predetermined by the type of sports. OBJECTIVE: To identify effects of the beta-stimulating training in recovery of adaptive reserves in athletes of different sports. MATERIAL AND METHODS: The study included young male athletes aged 18-22 years (n=1020), distributed according to the type of sports: group 1 - cyclic sports (n=387); group 2 - speed-strength sports (n=255); group 3 - single combat (n=31); group 4 - team sports (n=173); group 5 - complex-coordination sports (n=174). The main objective of the beta-stimulating training was to select a strategy to raise the beta rhythm level while muscles were relaxed. For each group, we identified training efficiency periods according to the lowest value of the attention index (θ/ß, c.u.), then we examined distribution of brain rhythms (α, %; ß, %; θ, %) according to EEG. The level of adaptive reserves was identified according to the heart rate variability (HRV) spectral analysis («VNS-Spektr¼, Neurosoft, Ivanovo). RESULTS: We identified following periods of the beta-stimulating training efficiency according to the attention index (θ/ß, c.u.): group 1 - 10th session (game variant); group 2 - 5th session (graphic and game variants); group 3 - 1st and 10th sessions (game variant), 5th session (graphic variant); group 4 (game variant) - 1st, 5th and 10th sessions; group 5 (game variant) - 5th and 10th sessions. The efficiency periods in the observed groups were accompanied by the following distribution of rhythms in the EEG structure: ß-rhythm - 45-60%; θ-rhythm - 20-35%, α-rhythm - 19-25%. During these periods, wave structure of the heart rhythm also changed: the activity of VLF waves increased (%); the proportion of HF waves decreased in the range of 23.3-31.59% in the groups 1, 2 and 3; the share of HF waves increased in the range of 32.3-39.8% in the group 4 at the 1st session and in the group 5 at the 10th session. The values of total power (TP, ms2) reduce at the 10th session in the groups 1, 3 and 4 and at the 5th session in the group 5. The vagosympathetic balance coefficient (LF/HF, c.u.) in the studied groups corresponds to the range of normal values; the values increased in the group 2 at the 5th session, in the groups 3 and 4 - at the 5th and 10th sessions, in the 5th group - at the 5th session. The index decreased in the groups 3 and 4 at the 1st session. The index was stable in the groups 1 and 5 at the 10th session of the training. CONCLUSION: Periods of the beta-stimulating training efficiency associated with the improvement of attention according to the lowest values of θ/ß (c.u.) are accompanied by changes in the modulation of the structure of brain rhythms and the wave structure of heart rate variability, optimizing the psychophysiological state of athletes depending on the type of sport, the number of sessions completed and the session variants chosen.
