Individual responses in biomarkers of health after marathon and half-marathon running: is age a factor in troponin changes?

Although strenuous physical activity is known to cause notable perturbations in blood chemistries, only few studies exist observing exercise-induced simultaneous changes in biomarkers of health status. We compared markers of muscle, cardiovascular, renal, hepatic and inflammatory status at baseline and at 3-h and at 48-h postrace in recreational runners who successfully completed either a marathon (mean age 27 ± 13 years, finishing time 199 ± 8 min, n = 4) or half-marathon (mean age 38 ± 13 years, finishing time 131 ± 6 min, n = 6) race. Significant postrace changes occurred in myoglobin (p < .001), creatinine kinase (p < .01), CK-MB-mass (p < .01), high sensitivity troponin I (p < .05), high sensitivity troponin T (p < .05), brain natriuretic peptide (p < .001), creatinine (p < .01), aminotransferase enzymes (p < .001 for AST and p < .01 for ALT), uric acid (p < .001) cortisol (p < .01), C-reactive protein (p < .05), leukocytes (p < .001), haematocrit (p < .05) and mean corpuscular volume (p < .01). In comparison between the two types of exercise, marathon running lead to more pronounced responses in myoglobin, CK-MB-mass, ALT, AST, lactate and phosphate. Notable elevations in troponin levels were observed only in young participants (<30 years), most strikingly in those ≤20 years of age. The data indicates that prolonged running leads to distinct biomarker alterations, which should be considered in the assessment of health status after recent acute bouts of strenuous exercise. The observations suggesting more pronounced cardiac troponin responses in young individuals warrant further studies in larger populations.