Live high, train low - influence on resting and post-exercise hepcidin levels

The post-exercise hepcidin response during prolonged (>2weeks) hypoxic exposure is not well understood. We compared plasma hepcidin levels 3h after exercise [6x1000m at 90% of maximal aerobic running velocity (vVO(2max))] performed in normoxia and normobaric hypoxia (3000m simulate altitude) 1week before, and during 14days of normobaric hypoxia [196.2 +/- 25.6h (median: 200.8h; range: 154.3-234.8h) at 3000m simulated altitude] in 10 well-trained distance runners (six males, four females). Venous blood was also analyzed for hepcidin after 2days of normobaric hypoxia. Hemoglobin mass (Hb(mass)) was measured via CO rebreathing 1week before and after 14days of hypoxia. Hepcidin was suppressed after 2 (Cohen's d=-2.3, 95% confidence interval: [-2.9, -1.6]) and 14days of normobaric hypoxia (d=-1.6 [-2.6, -0.6]). Hepcidin increased from baseline, 3h post-exercise in normoxia (d=0.8 [0.2, 1.3]) and hypoxia (d=0.6 [0.3, 1.0]), both before and after exposure (normoxia: d=0.7 [0.3, 1.2]; hypoxia: d=1.3 [0.4, 2.3]). In conclusion, 2weeks of normobaric hypoxia suppressed resting hepcidin levels, but did not alter the post-exercise response in either normoxia or hypoxia, compared with the pre-exposure response.