Objective: Exercise leads to an increase in cardiac troponin I (cTnI) in healthy, asymptomatic athletes after a marathon. Previous studies revealed single factors to relate to post-race cTnI levels. Integrating these factors into our study, we aimed to identify independent predictors for the exercise-induced cTnI release.Design: Observational study.Methods: Ninety-two participants participated in a marathon at a self-selected speed. Demographic data, health status, physical activity levels and marathon experience were obtained. Before and immediately after the marathon fluid intake was recorded, body mass changes were measured to determine fluid balance and venous blood was drawn for analysis of high-sensitive cTnI. Exercise intensity was examined by recording heart rate. We included age, participation in previous marathons, exercise duration, exercise intensity and hydration status (relative weight change) in our model as potential determinants to predict post-exercise cTnI level.Results: cTnI increased significantly from 14±12 ng/L at baseline to 94±102 ng/L post-race, with 69% of the participants demonstrating cTnI levels above the clinical cut-off value (40 ng/L) for an acute myocardial infarction. Linear backward regression analysis identified younger age (β=-0.27) and longer exercise duration (β=0.23) as significant predictors of higher post-race cTnI levels (total r=0.31, p<0.05), but not participation in previous marathons, relative weight change and exercise intensity. Conclusion:We found that cTnI levels significantly increased in a large heterogeneous group of athletes after completing a marathon. The magnitude of this response could only be partially explained, with a lower age and longer exercise duration being related to higher post-race cTnI levels.

No abstract

Donating blood influences psychological and hormonal stress response patterns. The response patterns differ between women and men, first-time and experienced donors and between donors high and low on non-acute stress.