Dynamics of the myocardial damage marker troponin T in elite biathlonists at the stages of the early season

Aim of the study: To study the quantitative dynamics of the myocardial damage marker troponin T (cTnT) in elite biathlonists as a response to the cyclic training aids used at the stages of the early season during the annual training cycle. Methods: The study involved 23 biathlonists undergoing centralized training as members of the national team of the Russian Federation. Serum cTnT quantitation was performed by means of electrochemiluminescent assay using Elecsys Troponin T hs reagent kit (Roche Diagnostics, Germany). Results: The mean group cTnT blood level in biathlonists did not exceed the upper limit of cardiac marker reference range established for healthy men (< 14 pg/ml). cTnT concentration of at the general preliminary stage was significantly higher than at the special preliminary stage ( p < 0.05), whereas statistically significant differences between the special preliminary and precompetition stages were not found ( p > 0.05). The maximum cTnT levels in the group of athletes were recorded in May and June, in July its concentration decreased at the trend level ( p > 0.05), then from August to October a significant decrease was documented ( p < 0.05). Conclusion: The low ALT and AST tissue specificity does nor reliably reveal functional myocardial overload as the response to physical exertion. In order to stratify the risk athletes with abnormal blood cTnT levels are recommended to diagnose the cardiovascular system within the in-depth biomedical observation, since it cannot be excluded that repeated bouts of endurance exercise, each causing subclinical effects, may have a cumulative effect on cardiac structure or function.