Share this article on:

Myocardial Stress after Competitive Exercise in Professional Road Cyclists

KÖNIG, DANIEL; SCHUMACHER, YORK OLAF; HEINRICH, LOTHAR; SCHMID, ANDREAS; BERG, ALOYS; DICKHUTH, HANS-HERMANN

Medicine & Science in Sports & Exercise: October 2003 - Volume 35 - Issue 10 - p 1679-1683
doi: 10.1249/01.MSS.0000089248.37173.E7
BASIC SCIENCES: Original Investigations

KÖNIG, D., Y. O. SCHUMACHER, L. HEINRICH, A. SCHMID, A. BERG, and H.-H. DICKHUTH. Myocardial Stress after Competitive Exercise in Professional Road Cyclists. Med. Sci. Sports Exerc., Vol. 35, No. 10, pp. 1679–1683, 2003.

Purpose Based on the determination of cardiac troponin (cTnT), brain natriuretic peptide (BNP), and echocardiographic measurements, recent investigations have reported myocardial damage and reversible cardiac dysfunction after prolonged endurance exercise in apparently healthy subjects. In the present study, we investigated the myocardial stress reaction in professional endurance athletes after strenuous competitive physical exercise.

Methods Eleven highly trained male professional road cyclists (age 27 ± 4 yr; V̇O2peak 67 ± 5 mL·kg−1·min−1; training workload 34,000 ± 2,500 km·yr−1) were examined. The following parameters were determined before and after one stage of a 5-d professional cycling race: BNP, cTnT (third-generation assay that shows no cross reactivity with skeletal TnT), creatine kinase (CK), creatine kinase MB (CKMB), myoglobin (Myo), and urea. All participants were submitted to a careful cardiac examination including echocardiography and stress ECG.

Results None of the athletes showed pathological findings in the cardiac examination. CK (P < 0.01), CKMB (P < 0.05), and Myo (P < 0.01) were increased after the race. Normal postexercise cTnT levels indicate that the increase in CK, CKMB, and Myo was of noncardiac origin. In contrast, BNP rose significantly from 47.5 ± 37.5 to 75.3 ± 55.3 pg·mL−1 (P < 0.01). Pre- and postexercise values of BNP as well as the individual exercise-induced increase in BNP were significantly correlated with age (R2 = 0.68, R2 = 0.66, and R2 = 0.58, respectively; P < 0.05).

Conclusion Strenuous endurance exercise in professional road cyclists does not result in structural myocardial damage. The rise in BNP in older athletes may reflect a reversible, mainly diastolic left ventricular dysfunction. This needs to be confirmed by larger trials including different intensities, sports, and age groups.

Center for Internal Medicine, Department of Rehabilitation, Prevention and Sports Medicine, Freiburg University Hospital, GERMANY

Address for correspondence: Dr. Daniel König, University Hospital Freiburg, Center for Internal Medicine, Department of Rehabilitation, Prevention and Sports Medicine, Hugstetter Straβe 55, D-79106 Freiburg im Breisgau, Germany; E-mail: Dani@msm1.ukl.uni-freiburg.de.

Submitted for publication January 2003.

Accepted for publication May 2003.

©2003The American College of Sports Medicine