Influence of acute physical exercise on emerging muscular biomarkers.

Background: Although there is comprehensive information on traditional biomarkers of muscle and cardiac damage following exercise, less is known on the kinetics of innovative markers, including ischemia modified albumin (IMA), glycogen phosphorylase isoenzyme BB (GPBB), carbonic anhydrase III (CAIII) and heart-type fatty acid-binding protein (H-FABP) in athletes performing a sub-maximal exercise.

Methods: A total of 10 healthy trained Caucasian males performed a 21-km run. Blood samples were collected before the run, immediately after (post), 3, 6 and 24 h thereafter. Cardiac troponin I (cTnI), myoglobin, creatine kinase isoenzyme MB (CK-MB), GPBB, CAIII and H-FABP were assayed using a new diagnostic system based on protein biochip array technology. IMA was measured by a commercial colorimetric assay on a Roche Modular system P.

Results: Significant variations by one-way analysis of variance were observed for CK-MB (p=0.013), myoglobin (p<0.001), GPBB (p=0.029), H-FABP (p<0.001), CAIII (p=0.006), but not for cTnI (p=1.00) and IMA (p=0.881). In particular, values of all the biomarkers tested, but cTnI and IMA, increased significantly immediately after the run. GPBB and H-FABP values returned to baseline 6 and 3 h thereafter, those of CAIII, CK-MB and myoglobin remained significantly elevated from the pre-run value up to 24 h after the run. The major variation over pre-run values was recorded for myoglobin (nearly 4-fold increment), whereas CAIII, CK-MB, GPBB and H-FABP increased by 2.9-, 1.8-, 1.4- and 1.2-fold, respectively.

Conclusions: We conclude that a sub-maximal aerobic exercise influences the concentration of several markers of muscle damage. Except for IMA, not one of the emerging biomarkers tested can be safely used to rule out myocardial damage as well as cardiospecific troponins in patients who had undergone recent physical activity.