Effects of exercise on haematologic parameters, serum iron, serum ferritin, red cell 2,3-diphosphoglycerate and creatine contents, and serum erythropoietin in long-distance runners during basal training.

We studied 18 well-trained male long-distance runners during the basal training. Haematologic parameters, serum iron and ferritin, red cell 2,3-diphosphoglycerate (2,3-DPG) and creatine contents, serum erythropoietin were investigated before and after the daily training and were compared with a group of healthy untrained controls. Red blood cell parameters did not change with the training, even though they were significantly lower than in controls. However, a true anaemic state cannot be suggested because the haemoglobin values fell into the lower limit of the normal range, even before the exercise. A slight but significant increase of neutrophils was found after the exercise, while no alteration of platelet count was observed. Serum iron and ferritin ranged normally. No increase of red cell 2,3-DPG was observed after the exercise, but it was significantly higher than in controls. After the exercise red creatinine was slightly increased. The athletes' erythropoietin was higher than that of controls, and showed a further increase after the training.