Effects of iron supplementation in female athletes with low serum ferritin concentration.
Low serum ferritin concentrations are commonly found in female athletes. By studying the effects of an 8-week iron or placebo supplementation in 31 female athletes (aged 17-31 years), with an initial serum ferritin concentration less than or equal to 25 micrograms/l and blood hemoglobin 120 g/l, we investigated whether low serum ferritin values hinder aerobic performance. Serum ferritin concentration increased from 14 (25th and 75th percentile: 11, 21) to 26 (18, 36) micrograms/l in the iron-supplemented group, but remained at a low 11 (9, 17) micrograms/l in the placebo group (group difference after supplementation: p = 0.001). Before supplementation, blood hemoglobin concentration was not different in the two groups. After supplementation, however, the concentration in the iron group was 139 (135, 144) g/l and 128 (126, 134) g/l in the placebo group (group difference: p = 0.001). Iron supplementation did not affect blood lactate concentration or VO2max during an incremental ergometer test. Hence, aerobic performance was not impaired in nonanemic female athletes with serum ferritin 25 micrograms/l.
Fogelholm
M
M
Department of Nutrition, University of Helsinki, Finland.
Jaakkola
L
L
Lampisjärvi
T
T
D000293:Adolescent; D000328:Adult; D004032:Diet; D015444:Exercise / Q000502:physiology*; D005260:Female; D005293:Ferritins / Q000097:blood*; D006454:Hemoglobins / Q000378:metabolism; D006801:Humans; D007501:Iron / Q000008:administration & dosage*; D007773:Lactates / Q000097:blood; D019344:Lactic Acid; D010101:Oxygen Consumption; D011897:Random Allocation
D006454:Hemoglobins; D007773:Lactates; D019344:Lactic Acid; D005293:Ferritins; D007501:Iron