The relationship between iron status and perceived exertion in trained and untrained women.

The subjects for this study were 24 female, well-trained distance runners and 41 sedentary, female university students. On the basis of haematological measurements, the subjects were divided into four groups: a group with iron deficiency, non-anemic (normal haemoglobin and red cell count but serum ferritin less than 20 micrograms degrees 1-1) runners (IDR, n = 11), a group of runners with normal iron status (NR, n = 13), a group of sedentary women with normal iron status (NC, n = 26) and a group of iron deficient, non-anemic sedentary subjects (IDC, n = 15). Maximal oxygen uptake (VO2max) and lactate thresholds were determined during incremental bicycle ergometer exercise testing and on separate occasions the ratings of perceived exertion (RPE) were assessed at 25, 50, 75 and 90% VO2max using Borg's scale. There were no differences in the relationship between RPE and work load groups of runners or sedentary subjects with normal and deficient iron status. Iron deficiency did not affect VO2max and lactate thresholds. However, low body iron stores (serum ferritin level below 20 micrograms degrees 1-1) without overt anemia was associated with increased venous blood lactate concentration after maximal exercise load. This study demonstrated that physical work capacity and RPE were not affected by iron deficiency without anemia either in trained or untrained women.