Puhach, Y. ., N. . Pashchenko, and T. . Lyakhova. “Operational Methods of Estimating the Current Functional sportsman’s State in the System of Training Process”. Slobozhanskyi Herald of Science and Sport, no. 6(80), Dec. 2020, pp. 73-80, https://journals.uran.ua/index.php/1991-0177/article/view/224735.