The impact of exercise intensity on the release of cardiac biomarkers in marathon runners

Eur J Appl Physiol. 2011 Dec;111(12):2961-7. doi: 10.1007/s00421-011-1922-3. Epub 2011 Mar 27.


We sought to determine the influence of exercise intensity on the release of cardiac troponin I (cTnI) and N-terminal pro-brain natriuretic peptide (NT-proBNP) in amateur marathon runners. Fourteen runners completed three exercise trials of the same duration but at exercise intensities corresponding to: (a) a competitive marathon [mean ± SD: heart rate 159 ± 7 beat min(-1), finish time 202 ± 14 min]; (b) 95% of individual anaerobic threshold [heart rate 144 ± 6 beat min(-1)] and; (c) 85% of individual anaerobic threshold [heart rate 129 ± 5 beat min(-1)]. cTnI and NT-proBNP were assayed from blood samples collected before, 30 min and 3 h post-exercise for each trial. cTnI and NT-proBNP were not different at baseline before each trial. After exercise at 85% of individual anaerobic threshold cTnI was not significantly elevated. Conversely, cTnI was elevated after exercise at 95% of individual anaerobic threshold (0.016 μg L(-1)) and to an even greater extent after exercise at competition intensity (0.054 μg L(-1)). Peak post-exercise values of NT-proBNP were elevated to a similar extent after all exercise trials (P < 0.05). The upper reference limit for cTnI (0.04 μg L(-1)) was exceeded in six subjects at competition intensity. No data for NT-proBNP surpassed its upper reference limit. Peak post-exercise values for cTnI and NT-proBNP were correlated with their respective baseline values. These data suggest exercise intensity influences the release of cTnI, but not NT-proBNP, and that competitive marathon running intensity is required for cTnI to be elevated over its upper reference limit.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Athletic Performance / physiology
  • Biomarkers / blood
  • Cohort Studies
  • Exercise / physiology*
  • Exercise Test / methods
  • Heart / physiology*
  • Heart Rate / physiology
  • Humans
  • Male
  • Myocardium / metabolism
  • Natriuretic Peptide, Brain / blood*
  • Peptide Fragments / blood*
  • Physical Endurance / physiology
  • Running / physiology*
  • Troponin I / blood*


  • Biomarkers
  • Peptide Fragments
  • Troponin I
  • pro-brain natriuretic peptide (1-76)
  • Natriuretic Peptide, Brain