Abstract

A student had haemoglobin in the urine after running but not after cycling. The haemoglobinuria was related to the hardness of the surface on which he ran and to his running style. The concentration of haptoglobin in his plasma was less than normal. This was most pronounced after he had been running, when haptoglobin had combined with free haemoglobin, but the concentration was also low when there had been no haemolysis for six weeks. Thus two factors combined to give him haemoglobinuria: lysis of red cells by mechanical damage and lack of haptoglobin to combine with liberated haemoglobin.