“…Greco-Roman wrestlers has shown that there is no unified approach to assessing the adaptive mechanisms of body energy systems at the pre-competition stage, which indicates the novelty of this study. Previously, performed works have shown the demand for the study of the control of heart rate variability in strength sports athletes [1], [2], [3], [4]; the control of biochemical parameters of athletes' training level by the example of weightlifters and martial arts athletes [5], [6]; the connection between heart rate and steroid hormones in their impact on muscle load [7], [8]; hormonal activity of testosterone and cortisol, and the effect of cortisol on the psych emotional state of strength sports athletes [8], [9], [10], [11], [12], [13]; control of thyroid-stimulating hormone during physical activity [14], [15]; and complex diagnostics of training level [16], [17], [18], [19], [20], [21].…”