Iron status and resting immune function in female collegiate swimmers

Iron deficiency may lead to anemia and may result in compromised endurance exercise performance. Iron deficiency has also been reported to adversely a ffect the immune system and has been associated with attenuation of natural killer cell (NK) activity. This study was conducted to examine the relatio nship between iron status and NK activity in highly conditioned female athl etes. Ten collegiate female swimmers (SWM) and 9 inactive females (SED) par ticipated in this investigation. Resting blood samples were obtained and an alyzed for serum iron and ferritin. NK activity (% lysis) was determined us ing a whole blood method (Cr-51 release assay). No significant relationship was found between iron and NK activity (r = 0.55, p = .09), nor between se rum ferritin and NK activity (r = 0.33, p = .35) for SWM. ANOVA revealed si gnificantly greater NK activity for SWM (51.63 +/- 15.79%) versus SED (30.3 4 +/- 13.67%). Serum ferritin levels were not significantly different betwe en SWM (20.38 +/- 8.62 etag (.) ml(-1)) and SED (16.79 +/- 10.53 etag (.) m l(-1)), nor were iron values different between groups (16.54 +/- 2.17 mu mo l (.) L-1 SWM; 11.92 +/- 2.61 mu mol (.) L-1 SED). A significant relationsh ip between iron status and resting immune function could not be established . Exercise training may affect NK activity; however, the influence of iron status on immune function requires further evaluation.