Effects of Iron Supplementation on Skeletal Muscle Properties in Females With Suboptimal Iron Storage

The goal of this clinical trial is to learn whether oral iron supplementation will increase skeletal muscle iron storage and its effects on exercise capacity in females with suboptimal iron status. The study will include healthy females, ages 18-40, who either have suboptimal or optimal iron stores. The main questions it aims to answer are: * Does iron supplementation increase skeletal muscle iron storage and alter the expression of iron-related and mitochondrial proteins? * Does iron supplementation improve single-leg exercise performance? * Is serum ferritin correlated with the abundance of iron-related proteins in skeletal muscle? Researchers will compare outcomes from females with suboptimal iron status who receive oral iron supplementation to those who receive a placebo to see if supplementation improves muscle iron storage, protein expression, and exercise performance. Additionally, a non-intervention control group with optimal iron status will be included to assess baseline differences. Participants will: \- Be randomly assigned to receive 150 mg elemental iron or placebo (maltodextrin) every other day for 12 weeks Complete pre- and post-supplementation testing, including: * Blood draws to assess iron status * Skeletal muscle biopsies to analyze protein content * Whole-body and single-leg exercise tests to assess performance * Controls will undergo baseline-only testing to compare physiological and biochemical markers