Exertional rhabdomyolysis during a 246-km continuous running race

Background: To evaluate the effect of continuous, moderate-intensity ultraendurance running exercise on skeletal muscle and hepatic damage, as indicated by serum enzyme activity measured immediately following the race. Methods: Thirty-nine runners of the Spartathlon race (a 246-km continuous race from Athens to Sparta, Greece) who managed to complete the race within the 36-h limit participated in this study. Mean finishing time of the study participants was 33.3 +/- 0.5 h and their average age, height, and body mass were 41 +/- 1 yr, 174 +/- 1 cm, and 67.5 +/- 1.1 kg, respectively. Blood samples, taken a day before and immediately after completion of the race, were assayed for the following variables: creatine kinase (CK), lactate dehydrogenase (LDH), aspartate aminotransferase (AST), alanine aminotransferase (ALT), and gamma-glutamyltransferase (gamma-GT). Results: A dramatic increase in most of muscle and liver damage indicators was observed. The mean values for CK, LDH, AST, and ALT after the race were 43,763 +/- 6,764, 2,300 +/- 285, 1,182 +/- 165, and 264 +/- 37 (IUL-1)-L-., respectively. These values were 29,384 +/- 4,327, 585 +/- 89, 5,615 +/- 902, and 1,606 +/- 331% higher than the corresponding values before the race (P < 0.001) for CK, LDH, AST, and ALT, respectively. However, there was not a significant increase in gamma-GT levels. Conclusion: Muscle and liver damage indicators were elevated at the highest level ever reported as a result of prolonged exercise, although no severe symptoms that required hospitalization were observed in any of the participants. The data suggest that even moderate-intensity exercise of prolonged duration can induce asymptomatic exertional rhabdomyolysis.