Abstract

In 15 subjects, amateur long-distance runners, the effect of marathon run on the functional status of skeletal muscles was assessed by studying creatine kinease (CK) activity and concentrations of urea and glucose in blood sampled from fingertips 1 h before and 15 min after the run. The exercise resulted in significant increases in plasma CK and CKMB activities and in urea concentration while blood glucose level remained unchanged. These were true for all subjects together, as well as for those whose total run time was short (Subgroup A) or long (Subgroup B). However, the post-run CK and CKMB activities were significantly lower in Subgroup A than in Subgroup B. Post-run activities of CK and CKMB were significantly, positively correlated with each other but not with the total run time or with the declared training experience. It was concluded that all subjects were sufficiently adapted to prolonged exercises to complete the marathon run although they markedly differed in their fitness. Verf.-Referat