Marathon race has been shown to increase serum activities of AST and ALT even in healthy individuals. It has not been clarified whether the increase is due to liver damage or soly to the muscle. Therefore we reevaluated the results of liver function tests. Additionally, serum guanase activity (GU) and serum hyarulonate concentrations (HY) were determined in a marathon race (42.195 km). The subjects were 4 male and 1 female runners. The records of marathon were 246 ± 12 mins.
　As a result, there was a significant rises in CK, LDH, AST, ALT immediately or one day after the race. A high correlation was shown between CK and each of AST and ALT (r=0.88, r=0.62, respectively). Although there was no correlation between CK, HY and GU also rose one day after the race.
　Our results suggest that the elevation of AST and ALT were not sufficient to estimate injured liver function in the presence of muscle damage. However, the increase in GU that exist in hepatocyte specifically and the elevation of serum HY that was internalized and degraded in liver endothelial cells suggest that the marathon race affect not only muscle cells but also both hepatocyte and hepatic sinusoidal endothelia.

DESCENTE SPORTS SCIENCE Vol.18/THE DESCENTE AND ISHIMOTO MEMORIAL FOUNDATION FOR THE PROMOTION SPORTS SCIENCE