Voluntary Isocapnic Hyperpnea in Hypoxia to Mitigate Acute Mountain Sickness

During the experimental session, they additionally performed a 5-minute VIH session (20 breaths/minute) after 1 hour of hypoxic exposure. Isocapnic BreathWayBetter devices (Isocapnic Technologies Inc., Kelowna, British Columbia, Canada) equipped with 6-liter breathing bags were employed to perform VIH. The accompanying Isocapnic mobile app was used to guide breathing rhythm and monitor session duration.