Abstract
<jats:p>Relevance. The complexity of the practical implementation of improving the training system in bodybuilding at different stages lies in the use of sufficiently diverse and not always justified methods of load correction and methods of diagnosing the level of resistance of the body systems of athletes of different age groups. Objective. To investigate the characteristics of adaptive-compensatory reactions in adolescent novice bodybuilders with different types of heart rate regulation when using strength training models that vary in intensity and volume. Methods. Forty-eight novice bodybuilders aged 15-16 were examined. Two groups were formed according to the type of heart rate regulation: normotonic and sympathotonic. To assess adaptive-compensatory responses to test trials under three strength training regimes, the heart rate variability method was used. Results. It was found that in response to such a stress stimulus, after using exercise mode ―A‖, we recorded a weakening of the central sinus rhythm regulation circuit in both the first (VLF -3.3%) and second (VLF -3.9%) groups of athletes. At the same time, in the representatives of the first group, we recorded a decrease in the vegetative balance (LF/HF -5.9%), and in the athletes of the second group, on the contrary, we observed an increase in the level of tension of the heart rhythm regulation systems (LF/HF +5.9%). It was established that after using the ―B‖ load regime, there were no significant changes in the power of the low-frequency spectrum of cardiac intervals (LF) in response to the proposed stress stimulus in both groups of participants. At the same time, there were also no changes in the level of parasympathetic tone (HF) activity after the completion of this test in novice bodybuilders in the first group. However, in the athletes of the second group, in response to this test load, an increase in the power of the HF indicator by 8.0% was recorded compared to the results found at the beginning of the study. Conclusions. It was found that in adolescent athletes with different types of heart rate regulation (normotonic and sympathotonic) who have a certain (3±0.3 years) experience in bodybuilding, only when using moderate intensity and volume loads during the test (mode ―B‖), there is a shift in the vegetative balance towards parasympathetic activity against the background of a weakening of the central sinus rhythm regulation circuit and a decrease in sympathetic tone.</jats:p>