The blunted post-exercise hepcidin response was most likely due to participants' low mean basal serum ferritin levels, ranging from 25.4 ng/mL during the early follicular phase to 29.2 ng/mL during the luteal phase, which is lower than the 35 μg/L cut off for stage 1 iron deficiency (Barba-Moreno et al., 2020). The gene discussed is HAMP; the disease is Iron deficiency anemia.