The Impact of Iron Supplementation on Athletic Performance in Elite-Level Female Athletes–A Systematic Review

ABSTRACT Iron deficiency (ID) in nonanemic athletes has become more prevalent, creating a need to investigate the relationship between iron supplementation and iron deficiency in female athletes who are not anemic. The objective of this systematic review was to determine the impact of iron supplementation on athletic performance in iron-deficient, nonanemic (IDNA) female athletes. The search strategy was conducted in February 2022 using PubMed and CINAHL databases. Nine records that focused only on IDNA female athletes were included in the review, with a total of 355 female participants. The inclusion criteria were adult female athletes found to be IDNA. Iron supplementation of any form, dose, or duration and athletic performance measures were used. The exclusion criteria included adolescents, being injured, consuming other supplements or medications, or not measuring athletic performance. Five studies in this review concluded that iron supplementation improved iron status and enhanced physiological adaption. However, the other studies found that iron supplementation did not affect training. Some limitations in the studies reviewed include small sample size, shorter training duration, broad training regimens, exercise protocol, and measurement timing. Further determination of the level at which iron supplementation should be considered for female athletes who are IDNA is warranted.