Adult and young highly skilled Greco-Roman wrestlers are trained using the same training program. The use of the standard models of testing loads and research methods for adult and young highly skilled wrestlers allowed to reveal significant differences in the level of their general and special training. A comparative analysis of the test data obtained from adult and young highly skilled wrestlers in adapting the cardiovascular system to the cycloergometric load and analyzer systems to the special power load has not yet been conducted for these athletes. The purpose of the study is to determine the informative value of diagnostic methods for determining the training of highly skilled Greco-Roman wrestlers of different age. The main results of the study are the substantiation of the informative value of tests and research methods, which most fully describe special training of wrestlers from different age groups. A lower level of strength performance and coordination abilities, increased fatigue of the central and neuromuscular systems, as well as intensity of the circulatory system adaptation during the adaptation to the testing load on the cycle ergometer were determined in the surveyed contingent of young athletes, compared with adult wrestlers. The used set of tests and research methods is informative for determining the training level of highly skilled wrestlers of different age. Conclusion. The use of complex diagnostics of cardiovascular and analyzer systems allows to determine the physical and functional body reserves of young and adult wrestlers and factors that limit performance, and necessitates the development of individual training programs for juniors in their sports improvement.