Cardiac Troponin Elevation After Long-Distance Cycling is Associated with Oxidative Stress and Exercise Intensity: An Observational Study

Background: To date, the mechanisms of post-exercise cardiac troponin elevation are debatable. Previous studies have reported that oxidative stress happens after extended exercise. Objectives: This study purposed to establish the association between the elevation of malondialdehyde (MDA), which is a marker of oxidative stress, and cardiac troponin-I (cTn-I) after prolonged cycling. Methods: Ninety-two males in Indonesian cycling tours participated in the present study. Baseline and post-exercise blood specimens were obtained to define MDA and cTn-I levels. The elevations of MDA and cTn-I were determined as positive differences of post-cycling MDA and cTn-I levels to the baseline, respectively. Results: Eighty-eight participants (age, mean = 45.3 years old, [SD]:11.47; body mass index (BMI), mean=24.2 kg/m2, [SD]: 3.03) finished the cycling tours. Subjects’ characteristics were comparable based on the touring category, except for the family history of coronary artery disease, high-density lipoprotein cholesterol level, neutrophil count, resting heart rate, exercise intensity, and cTn-I elevation. MDA significantly escalated at the level of 210.90 µmol/mL at post-exercise, from 190.18 µmol/mL at baseline. cTn-I also increased at the level of 13.65 ng/dL from 5.16 ng/dL. The elevation of MDA was related to the elevation of cTn-I. Elevation of cTn-I after prolonged cycling was contributed by elevation of MDA and exercise intensity. Conclusions: The present findings support existing confirmation that cTn-I elevation after prolonged exercise is related to oxidative stress and exercise intensity.