Abstract

In this paper, we tried to estimate the muscle damage by measuring the serum myoglobin levels after physical exercise. The results are summarized as follows. 1. Five cases with disorders mainly of skeletal muscle due to physical exercise or sports were presented. They had been healthy in ordinary life. Serum myoglobin levels were serially measured in stepping-down exercise for case 1, treadmill-exercise for case 2 and case 4, sports training for case 3, and 5 km running for case 5, and compared with those obtained by healthy subjects. In all cases, serum myoglobin levels were much elevated up to 1.850 ng/ml suggestive of myopathy and pigmenturia (hemoglobinuria) was noticed. These results suggest that prediction of sports disorder may be possible by measuring serummyoglobin after exercise loading, which is also useful to detect latent myopathy. 2. The elevation of serum myoglobin levels due to physical exercise before and after one week of group training were compared in Rugby players and Japanese fencers and no apparent difference between the levels was found. These data suggest that such a grade of training may be insufficient both in strength and frequency to have adapted them completely to the exercise. 3. There was a significant correlation (r = 0.81) between blood lactic acid values after exercise x duration of exercise and peak serum myoglobin values after exercise. This suggests that damage of muscle and its membrane induced by lactic acid accumulation is a possible cause of myoglobin release from the muscle cell. These results indicate that measurement of serum myoglobin after exercise is useful for prediction of muscle disorder induced by sports. Verf.-Referat