EVALUATION OF IRON-METABOLISM INDEXES AND THEIR RELATION WITH PHYSICAL WORK CAPACITY IN ATHLETES

Objective-To evaluate the relation between iron status and physical wo rking capacity, and to assess the effect of oral iron treatment on the se variables, in athletes with borderline iron status. Methods-Blood h aemoglobin (Hb), packed cell volume (PCV), red blood cell count (RBC), serum iron, total iron binding capacity (TIBC), and ferritin determin ations were compared in 71 male and 18 female athletes participating i n various sports and in matched male (n = 11) and female (n = 8) contr ols. The first aim was to assess the relations between these variables and performance in a physical work capacity test (PWC170). Oral iron treatment (175-350 mg ferrous fumarate daily) was provided for three w eeks to six male and five female athletes with borderline Hb concentra tions, to determine the effects of such treatment on both iron status and performance. Results-Among females, handball players had the lowes t serum ferritin concentrations (P < 0.05), the highest TIBC values, a nd lowest PWC170 scores (P < 0.01); runners had the highest ferritin c oncentrations and PWC170 scores (P < 0.01). There were significant cor relations (P < 0.01) between PWC170 and PCV, serum ferritin, and trans ferrin saturation of female athletes. Hb, serum iron, serum ferritin, and transferrin saturation increased with iron treatment in both males (P < 0.01) and females (P < 0.05). Conclusions-Serum ferritin determi nation may prove a valuable addition to the screening of athletes and may indicate the need for iron treatment, even though a causal effect on improvement of work capacity may not be present.