Sports Anemia: A Review of the Current Research Literature.

In brief: A small percentage of athletes are anemic, and a substantial number have hemoglobin concentrations that are less than optimal for endurance performance. Possible causes of sports anemia are plasma volume expansion, reduced hemoglobin synthesis and/or erythropoiesis, and increased destruction of RBCs. Physicians should screen athletes for anemia, suboptimal hemoglobin, and the factors that apparently increase the risk of these conditions: (1) a diet that is low in iron, protein, vitamin C, vitamin B12, and/or folic acid; (2) high rates of iron loss; and (3) very intense training, especially at the outset of an exercise program. Treatment depends on the cause but may include iron supplementation and training modifications.