European Jourrnal of Eur J App! Physiol (1983) 52: 57-61 > AniJjerd Phyogy and Occupational Pflys'ology r Spl.n9er-Ver.ag1983 Transitory Hematologic Effects of Moderate Exercise Are Not Influenced by Iron Supplementation* Jack Hegenauer t , Linda Strausel, Paul Saltman', Diana Dann 2 , James White 2 , and Ralph Green 3 ' Department of Biology (B-022). University of California. San Diego. La Jolla. CA 92093. USA 2 Department of Physical Education, University of California. San Diego. La Jolla. CA 92093 Department of Clinical Research, Scripps Clinic and Research Foundation. La Jolla. CA 92037 Summary. A young women's exercise/fitness class Key words: Sports anemia - Iron supplements - tested the idea that administration of supplemental Exercise - Hematologic changes - Hemoglobin iron would prevent "sports anemia" that may develop during exercise and training and improve iron status of exercising females of menstrual age. Fifteen women (aged 18-37) were selected for each of three Introduction treatment groups: (1) no supplemental iron; (2) 9 Work with humans and laboratory animals has shown mg d-i of Fe; and (3) 18 mg d-' of Fe (1 US ionkretment lorardac stre ss.Ig n Recommended Daily Allowance). Women exercised that iron treatment lowers cardiac stress In general. at approximately 85% of maximal heartrate for work performance measures seem directly correlated progressively increasing lengths of time in a jogging with, and post-exercise heartrate and blood lactate program and worked up to 45 min of exercise 4 concentration seem inversely proportional to. the d * week-' for 8 weeks. Hematologic analysis was hemoglobin concentration ([Hb]) of blood (Gardner performed in weeks 1, 5, and 8. A significant decline et al. 1977). Observations that iron-supplemented in hemoglobin (Hb) concentration and hematocrit subjects showed increased treadmill endurance and (Hct) was observed at week 5 when all data were lower heartrate than untreated subjects with the same examined without regard for iron intake; these red [Hb] led Ohira et al. (1979) to postulate non-Hb cell indices returned to pre-exercise levels by week 8. related effects of iron that are manifested indepe Reduction of mean cell hemoglobin concentration dently of oxygen-carrying capacity of blood. No (MCHC) indicated that the midpoint decline was not published studies, however, have yet addressed the caused by simple hemodilution during exercise. question of the effects of iron on non-anemic subjects Serum ferritin (SF) concentration changed in parallel to investigate whether oral iron supplementation with Hb and Hct. Although the midpoint decline in might affect the same phenomena in healthy, hema- SF was not statistically significant, it ruled out the tologically normal individuals. possibility that turnover of red cell iron was directed The phenomenon of "spons anemia", a reduction to storage. Lowered MCHC and SF suggested lower of IHb] which is most commonly associated with availability of iron during the synthesis of a new strenuous athletic training (Yoshimura 1970; Hund- generation of red cells. Few iron treatment effects of ing et al. 1981), has also been noted when normally magnitude were observed. Iron did not prevent the sedentary individuals begin an exercise program midpoint decline in Hb concentration. Iron intake did (Puhl and Runyon 1980). The objective of our study not affect SF, serum iron, transferrin saturation, or was to determine if administration of supplemental final Hb, and Hct. Dietary iron availability thus does Iron dunng the course of a moderate exercise not appear to play a role in the phenomenon of program would prevent this "sports anemia". "sports anemia". Temporary alteration ofprioritiesfor iron needs during exercise, perhaps for muscle myo- Methods globin, maybe responsible forthis transitory "anemia". Selection of Subjects and Study Protocol * Supported by the Health Sciences Division, Shaklee Coopera- Women university students and staff volunteered topanicipate ina tion. Hayward, California fitness class designed to introduce relatively sedentary individuals Offprinz requests to: J. Hegenauet at the above address to the benefits of moderate exercise. Subjects gave informed