Daily iron supplementation significantly improves maximal and submaximal exercise performance in WRA , providing a rationale to prevent and treat iron deficiency in this group .
Animal and human observational studies suggest that iron deficiency impairs physical exercise performance , but findings from r and omized trials on the effects of iron are equivocal .
Iron deficiency and anemia are especially common in women of reproductive age ( WRA ) .
Clear evidence of benefit from iron supplementation would inform clinical and public health guidelines .
Therefore , we performed a systematic review and meta- analysis to determine the effect of iron supplementation compared with control on exercise performance in WRA .
The effects of prelatent/latent iron deficiency on physical work capacity.
In order to examine the effects of mild iron deficiency on physical work capacity , 40 prelatent iron-deficient female endurance runners were studied before and after 8 wk of supplementation with either oral iron ( 320 mg ferrous sulfate ) or a matching placebo . Subjects underwent the following physical work capacity tests : the Wingate cycle ergometer test , the anaerobic speed test , the ventilatory threshold , VO2max , and maximal treadmill velocity during the VO2max test . Muscle biopsy sample s pre- and post-treatment were obtained from 17 of the subjects , and these were assayed for citrate synthase and cytoplasmic alpha-glycerophosphate dehydrogenase activity . Subjects were r and omly assigned to one of the treatment groups , and a double-blind method of administration of the supplements was used . The differences in improvement scores between the two groups on the work capacity and enzyme activity variables were statistically nonsignificant ( P greater than 0.05 ) . Serum ferritin values rose from a mean of 12.4 + /- 4.5 to 37.7 + /- 19.7 ng.ml-1 for the experimental group and from 12.2 + /- 4.3 to 17.2 + /- 8.9 ng.ml-1 for the controls ( P = 0.0025 ) , whereas hemoglobin levels remained fairly constant for both groups ( P = 0.6 ) . Eight weeks of iron supplementation to prelatent/latent iron-deficient , physically active females did not significantly enhance work capacity . Within the limitations of this study , the presence of a serum ferritin below 20 ng.ml-1 does not pose a significant h and icap to physical work capacity
Daily iron supplementation significantly improves maximal and submaximal exercise performance in WRA , providing a rationale to prevent and treat iron deficiency in this group .
Animal and human observational studies suggest that iron deficiency impairs physical exercise performance , but findings from r and omized trials on the effects of iron are equivocal .
Iron deficiency and anemia are especially common in women of reproductive age ( WRA ) .
Clear evidence of benefit from iron supplementation would inform clinical and public health guidelines .
Therefore , we performed a systematic review and meta- analysis to determine the effect of iron supplementation compared with control on exercise performance in WRA .