Work capacity after iron treatment as a function of hemoglobin and iron deficiency.
The relative importance of hemoglobin (Hb) and non-Hb iron for physical work capacity was studied in 45 adult male and female subjects, with a range of Hb and serum iron levels. Maximal work capacity, heart rate, venous blood lactate and serum protein were measured before and after 1 week of treatment with Imferon, i.v. Even though some non-Hb related effects on parameters indicative of maximal work capacity were found, the main factor was Hb related. Subjects with low Hb-high serum iron worked longer than ones with low Hb-low iron. When work performed was similar, the marginal Hb-low iron group had a higher blood lactate concentration than the high Hb-high iron and marginal Hb-high iron groups. The coefficient of correlation between serum iron and post-exercise lactate levels was -0.41 (p less than 0.05). Even though neither of these groups showed a Hb response within 1 week of iron treatment, the initial low serum iron groups had significantly lower heart rates at a given work load relative to subjects with high iron but with a similar Hb level. This occurred both at rest and during light to heavy exercise. These results suggest that a rather rapid benefit of iron treatment is gained in iron-deficient subjects with severe and moderate anemia which cannot be accounted for by Hb changes. Although the primary factor which affects the physical work capacity of iron-deficient anemic subjects seems to be the Hb level, there also seems to be a significant non-Hb related effect of iron treatment as well.
D000747:Anemia, Hypochromic / Q000097:blood / Q000188:drug therapy* / Q000503:physiopathology; D001803:Blood Transfusion; D005260:Female; D006339:Heart Rate; D006454:Hemoglobins / Q000032:analysis*; D006801:Humans; D007501:Iron / Q000097:blood / Q000627:therapeutic use; D007773:Lactates / Q000097:blood; D019344:Lactic Acid; D008297:Male; D010807:Physical Endurance
D006454:Hemoglobins; D007773:Lactates; D019344:Lactic Acid; D007501:Iron