Iron status of women distance runners, sprinters, and control women

Fasting blood samples from 11 women distance runners, 12 sprinters, and 11 moderately active women were examined to determine iron status. Dietary iron intake and bioavailability were analyzed from 3-day food diaries. Both distance runners and sprinters had lower hematocrits and haptoglobins than moderately active women. Distance runners had significantly lower ferritin (15.8 micrograms/l) than sprinters (32.8 micrograms/l), but moderately active women's ferritin (26.1 micrograms/l) was not significantly different than in the other groups. Five distance runners, two sprinters, and one moderately active woman had ferritins below 12 micrograms/l, which suggests iron depletion. Differences in hemoglobin, plasma iron, transferrin, and food iron intake were not significant among the three groups. Absorbable iron and heme iron intake were significantly lower for the distance runners and control women than the sprinters. The results suggest that low ferritin is more common among women who train for distance events than for sprints. This difference may by due to differences in bioavailability of food iron intake.