Sex differences in release of cardiac troponin T after endurance exercise

Context: Post-exercise cardiac troponin release has been extensively described in athletic groups but little attention has been given to any role of sex in mediating this phenomenon. Objective: We compared the release of cardiac troponin T (cTnT) after endurance running in training-experience, biological-age and maturity-matched young male and female runners. Materials and methods: Nineteen male (training history: 2.3 ± 1.0 years; mean age: 16.1 ± 1.2 years; Tanner stage: 3.7 ± 0.6) and 19 female (training history: 2.2 ± 1.0 years; mean age: 15.9 ± 1.4 years; Tanner stage: 4.0 ± 0.4) runners performed a 21 km run with “all-out” effort. Serum cTnT levels were assessed at pre-exercise (Pre-ex) and at 4 h post-exercise (Post-ex). Results: At Pre-ex, cTnT concentrations were below the 99th percentile value (10 ng.l⁻¹) in 32/38 runners. Post-ex cTnT increased in all subjects but the response was substantially higher (p < 0.05) in males [median (range): 210 (20–1360) ng.l⁻¹] than females [median (range): 80 (10–550) ng.l⁻¹]. At Post-ex, 95% (95% confidence interval: 75–99%) of males and 63% (95% confidence interval: 41–81%) of females (p < 0.05) had cTnT concentrations above the cut-off for acute myocardial infarction. Conclusions: The present data suggest that post-exercise cTnT elevation occurs in all runners but is augmented in young male compared to female athletes.