Bone marrow iron depression in competitive distance runners.

Suboptimal hemoglobin and serum iron have been reported in endurance athletes. In the present study peripheral blood, bone marrow cellularity and hemosiderin, serum iron and serum iron binding capacity were observed in 12 competitive distance runners. Hemoglobin, hematocrit, mean corpuscular volume and concentration, serum iron and iron binding capacity were within normal range. Peripheral blood showed mild hypochromia in six runners, bone marrow cellularity was reduced in two, while bone marrow hemosiderin granules were absent in seven and traces were seen in five. These data suggest that a proportion of highly trained distance runners have insufficient iron stores and need supplementation to balance their iron requirements.