Postgame elevation of cardiac markers among elite floorball players

Cardiac biomarker release after exercise is well documented in endurance sports, but neither the impact of intermittent high-intensity exercise nor the reproducibility has yet been established. Floorball, a popular sport in Scandinavia, involves intermittent periods of high-intensity exercise. This study aimed to determine the prevalence and reproducibility of elevated cardiac marker levels among elite floorball players after two games. Twenty-three healthy male elite floorball players of median age 19 years (range 16-34 years) participated in two standard games. Blood was drawn at three time points: pregame, immediately after, and 2 h after the game. Creatine kinase MB (CK-MB), myoglobin, and high-sensitivity cardiac troponin T (hs-cTnT) were measured. The results showed significantly elevated median postgame values in all markers. In both games, hs-cTnT exceeded the cutoff for myocardial damage (≥ 14 ng/L) 2 h postgame in the same six players. The major findings were that postgame cardiac hs-cTnT values among elite floorball players were significantly elevated and reproducible. The findings imply that extended investigations should incorporate evaluation of myocardial function and myocardial perfusion during exercise to seek the clinical significance and underlying mechanisms of elevated cardiac troponin after high-intensity exercise.