CHANGES IN IRON STATUS DURING COMPETITIVE SEASON IN FEMALE COLLEGIATESWIMMERS

We examined changes in iron status in 25 female varsity collegiate swi mmers over the course of a competitive season via weekly capillary blo od sampling. We also studied the effectiveness of moderate iron supple mentation (39 mg/day) in preventing expected changes in iron status vi a a double-blinded crossover design. On entry into the study, 17 of th e swimmers had depleted iron stores (plasma ferritin <12 mug/L) and 5 were anemic (Hb <120 g/L). After 5 wk of placebo treatment, hemoglobin decreased (greater-than-or-equal-to 6 g/L) in 44% and increased in 12 % of the subjects. After 5 wk of iron supplementation, hemoglobin decr eased in 16% and increased in 24% of the subjects. Likewise, after pla cebo treatment, plasma ferritin decreased (greater-than-or-equal-to 5 mug/L) in 24% and increased in 4% of the subjects, whereas iron supple mentation resulted in decreases in 4% and increases in 68% of the subj ects. In the absence of iron supplementation, hemoglobin levels decrea sed despite mean dietary iron intakes of 16.3 mg/day. These results sh ow that moderate iron supplementation is effective in preventing decli ne in the iron status of female collegiate swimmers during a competiti ve season, but a higher dose of iron may be necessary to reverse their iron-deficient state.