In IDNA adults  , iron supplementation is associated with reduced subjective measures of fatigue but not with objective improvements in physical capacity .
OBJECTIVE Iron supplementation in iron-deficiency anaemia is st and ard practice , but the benefits of iron supplementation in iron-deficient non-anaemic ( IDNA ) individuals remains controversial .
Our objective is to identify the effects of iron therapy on fatigue and physical capacity in IDNA adults .
Iron supplementation improves endurance after training in iron-depleted, nonanemic women.
Our objective was to investigate the effects of iron depletion on adaptation to aerobic exercise , assessed by time to complete a 15-km cycle ergometer test . Forty-two iron-depleted ( serum ferritin < 16 microg/l ) , nonanemic ( Hb > 12 g/dl ) women ( 18 - 33 yr old ) received 100 mg of ferrous sulfate ( S ) or placebo ( P ) per day for 6 wk in a r and omized , double-blind trial . Subjects trained for 30 min/day , 5 days/wk at 75 - 85 % of maximum heart rate for the final 4 wk of the study . There were no group differences in baseline iron status or in 15-km time . Iron supplementation increased serum ferritin and decreased transferrin receptors in the S compared with the P group . The S and P groups decreased 15-km time and respiratory exchange ratio and increased work rate during the 15-km time trial after training . The decrease in 15-km time was greater in the S than in the P group ( P = 0.04 ) and could be partially attributed to increases in serum ferritin and Hb . These results indicate that iron deficiency without anemia impairs favorable adaptation to aerobic exercise
In IDNA adults  , iron supplementation is associated with reduced subjective measures of fatigue but not with objective improvements in physical capacity .
OBJECTIVE Iron supplementation in iron-deficiency anaemia is st and ard practice , but the benefits of iron supplementation in iron-deficient non-anaemic ( IDNA ) individuals remains controversial .
Our objective is to identify the effects of iron therapy on fatigue and physical capacity in IDNA adults .