Hypoxia matters: comparison of external and internal training load markers during an 8-week resistance training program in normoxia, normobaric hypoxia and hypobaric hypoxia.

Purpose: To compare external and internal training load markers during resistance training (R) in normoxia (N), intermittent hypobaric hypoxia (HH), and intermittent normobaric hypoxia (NH).

Methods: Thirty-three volunteers were assigned an 8-week R program in either N (690 m, n = 10), HH (2320 m, n = 10), or NH (inspired fraction of oxygen = 15.9%; ~ 2320 m, n = 13).