Gunina L, Rybina I, Voitenko V. Laboratory diagnosis of overtraining in high performance sport. Science in Olympic Sport. 2021;3:16-25. DOI:10.32652/olympic2021.3_3

Objective. Based on the analysis and synthesis of data from scientific literature, to develop modern ideas about the opportunities in the laboratory diagnosis and to design a diagnostic algorithm for the identification and assessment of the severity of the overtraining syndrome in elite athletes.
Methods. Analysis and synthesis of current research data on the studied issue, as well as data from the Internet.
Results. Modern terminological characteristics of overtraining are presented; the main factors leading to the development of this syndrome in athletes are summarized, and algorithms of primary and refining diagnostic technologies are described. The most important role of changes in the athlete’s hormonal status that led to insufficient recovery and further development of overtraining, as well as the possibility of using calculated indicators to characterize disorders of anabolic and catabolic status of athletes underlying these pathological conditions are described. The most modern methodological approaches that allow for differential assessment of overtraining in sports are briefly reviewed.
Conclusion. Lack of timely diagnosis of the overtraining syndrome results in deterioration of the athlete's health. The basis for timely diagnosis of overtraining should be the following first-level tests: blood urea and creatinine, mean erythrocyte volume, and creatine phosphokinase activity. Timely assessment of myocyte integrity, oxidative stress parameters, proinflammatory cytokine content, and activity of marker enzymes will help the coach to change the structure of the training process and maintain the athlete's health.

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Received 11.10.2021