Iron Deficiency in Division III Male Cross Country Runners
The incidence of iron deficiency (without anemia) in males is 2% (CDC statistics), as compared with 14% in females. However, male distance runners and endurance athletes have increased iron losses due to excessive sweating, gastrointestinal bleeds, hematuria, and increased hemolysis due to foot strike (1). Iron deficiency, even with normal hemoglobin (Hb) values, may result in decreased athletic performance, decreased energetic efficiency during submaximal exercise, and increased muscle fatigue (2).
Purpose: To assess the iron status of the male cross country runners and identify subjects who are iron deficient.
Methods: Subjects were 37 males aged 18-22. The study was approved by the Institutional Review Board of the College, and all subjects signed informed consent forms. Three day diet records were collected during at the beginning of fall practice and analyzed to determine iron intake and food sources (heme vs. nonheme) using Diet Analysis Plus Version 7.0.1. Blood samples were collected at the beginning of the season and again after 12 weeks. Serum ferritin was analyzed using CALBIOTECH Ferritin ELISA and hemoglobin was analyzed using a HemoCue Whole Blood Hemoglobin System.
Results: Mean iron intake was 25 ±9 mg (RDA for males is 8 mg/day). Initial mean serum ferritin was 99 ±70 ng/mL; values <20 ng/mL may result in decreased athletic performance (3). Eight subjects (21.0%) had an initial serum ferritin <40ng/mL. Initial mean Hb was 14.8±1.1 g/dL; five subjects (13.0%) had Hb values ≤ 13.5 g/dL (normal range for males is 13.5-16.5 g/dL). Subjects who had low initial serum ferritin and Hb levels were educated to improve their dietary sources of iron and to consider the use of an iron supplement. Final mean serum ferritin was 126±80 ng/mL and mean Hb was 15.1±1.2 g/dL. After 12 weeks, only two (5%) of the original eight subjects with low serum ferritin values remained <40 ng/mL, and three (7.8%) still had Hb ≤13.5. However, two additional runners displayed Hb values ≤13.5 g/dL at the final reading.
Conclusion: Despite the fact that iron deficiency in the male population is only 2%, the male runners in this study had an incidence of 21.0%, which is high enough to warrant routine screenings for iron status.
Sarah Gervais presenting her research at the at the Northland Chapter of the American College of Sports Medicine, March, 2009, St. Cloud, MN
Sarah and her research partner, Jessica Walker, won third place in the poster competition.
To view Poster, click on link below:
|Research Advisors: Mani Campos PhD, Biology and Amy Olson PhD, RDN, LD, Nutrition|