Objective.—The study aimed to examine the physiological responses to acute normobaric hypoxia during an intermittent walking protocol.

Methods.—Twelve active healthy male participants completed a 125-minute test that involved rest and walking (50% V̇o_2max) during normoxic (20.93%O₂) and 2 hypoxic conditions (14%O₂ and 12%O₂). A range of physiological markers were measured throughout the test. Lake Louise Questionnaire scores and Environmental Symptoms Questionnaire cerebral scores were used as a measurement of acute mountain sickness symptoms.

Results.—Oxygen saturation, thermal sensation scale, heart rate, perceived thirst, core temperature, rating of perceived exertion, feeling state, and Δbody mass all positively correlated with the highest Lake Louise Questionnaire and Environmental Symptoms Questionnaire cerebral scores (P < .05) and were significantly different between the 3 conditions during the exercise phases.

Conclusion.—A range of physiological markers are associated with symptoms of acute mountain sickness following brief periods of hypoxic exposure.