Highly sensitive cardiac troponin T is not increased by strenuous eccentric exercise.

Mousavi et al1 recently reported that immediately after the completion of a full marathon, all athletes demonstrated elevated cardiac troponin T (cTnT) levels, with a median value of 0.31 g/L, greater than the 99% reference limit. This increase in cTnT was attributed to cytosolic release of the biomarker, not to the true breakdown of the myocyte. Similar results were also reported by Mingels et al,2 who observed that 86% of marathon runners had cTnT concentrations greater than the 99th percentile as measured by a novel highly sensitive cTnT (Hs-TnT) assay. Interestingly, Giannitsis et al3 found several patterns of Hs-TnT concentration changes during a continuous 216-km marathon, including cases with constantly low concentrations without changes as well as cases with early increases of Hs- TnT after the start of strenuous exercise. Koller and Schobersberger4 hypothesized, however, neither that the increase in cardiac troponin after marathon running is likely due to the cytosolic release of the biomarker nor that the release of cardiac troponin represents the true breakdown of the myocyte