The impact of short duration, high intensity exercise on cardiac troponin release.

Abstract

The aim of this study was to assess the appearance of cardiac troponins (cTnI and/or cTnT) after a short bout (30s) of 'all-out' intense exercise and to determine the stability of any exercise-related cTnI release in response to repeated bouts of high intensity exercise separated by 7days recovery. Eighteen apparently healthy, physically active, male university students completed two all-out 30s cycle sprint, separated by 7days. cTnI, blood lactate and catecholamine concentrations were measured before, immediately after and 24h after each bout. Cycle performance, heart rate and blood pressure responses to exercise were also recorded. Cycle performance was modestly elevated in the second trial [6·5% increase in peak power output (PPO)]; there was no difference in the cardiovascular, lactate or catecholamine response to the two cycle trials. cTnI was not significantly elevated from baseline through recovery (Trial 1: 0·06±0·04ngml(-1) , 0·05±0·04ngml(-1) , 0·03±0·02ngml(-1) ; Trial 2: 0·02±0·04ngml(-1) , 0·04±0·03ngml(-1) , 0·05±0·06ngml(-1) ) in either trial. Very small within subject changes were not significantly correlated between the two trials (r=0·06; P>0·05). Subsequently, short duration, high intensity exercise does not elicit a clinically relevant response in cTnI and any small alterations likely reflect the underlying biological variability of cTnI measurement within the participants.