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

Background: To date, the mechanisms of postexercise 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 troponinI (cTnI) after prolonged cycling.Methods: Ninetytwo males in Indonesian cycling tours participated in the present study. Baseline and postexercise blood specimens were obtained to define MDA and cTnI levels. The elevations of MDA and cTnI were determined as positive differences of postcycling MDA and cTnI levels to the baseline, respectively.Results: Eightyeight participants (age, mean = 45.3 years old, [SD]:11.47; body mass index (BMI), mean=24.2 kg/m^2 , [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, highdensity lipoprotein cholesterol level, neutrophil count, resting heart rate, exercise intensity, and cTnI elevation. MDA significantly escalated at the level of 210.90 µmol/mL at postexercise, from 190.18 µmol/mL at baseline. cTnI 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 cTnI. Elevation of cTnI after prolonged cycling was contributed by elevation of MDA and exercise intensity.Conclusions: The present findings support existing confirmation that cTnI elevation after prolonged exercise is related to oxidative stress and exercise intensity.