High Intraindividual Variability in the Response of Serum Erythropoietin to Multiple Simulated Altitude Exposures

Baranauskas, Marissa N., Timothy J. Fulton, Alyce D. Fly, Bruce J. Martin, Timothy D. Mickleborough, and Robert F. Chapman. High intraindividual variability in the response of serum erythropoietin to multiple simulated altitude exposures. . 23:85-89, 2022. To evaluate within-subject variability in the serum erythropoietin (EPO) response to multiple simulated altitude exposures. Seven physically active men and women (age 27 ± 3 years, body mass index = 24.6 ± 4.0 kg/m ) were exposed to normobaric hypoxia (fraction of inspired oxygen [F O ] = 0.14) for 12 hours on three separate occasions. Serum EPO concentrations were measured before exposure (0 hour), after 6 hours, and after 12 hours in hypoxia. The EPO response to hypoxia was calculated as percent change from 0 to 12 hours (ΔEPO ). Exposure time had a significant effect on EPO (