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Supramaximal Intensity Hypoxic Exercise and Vascular Function Assessment in Mice
Published on: March 15, 2019
Physiological responses to graded acute normobaric hypoxia using an intermittent walking protocol.
Alan Richardson1, Rosie Twomey, Peter Watt
1University of Brighton, Chelsea School Research Centre, Eastbourne, United Kingdom. a.j.richardson@brighton.ac.uk
Wilderness & Environmental Medicine
|December 23, 2008
Summary
Physiological responses like heart rate and body mass correlate with acute mountain sickness symptoms during intermittent walking in hypoxic conditions. These markers indicate discomfort and physiological strain from reduced oxygen availability.
Area of Science:
- Exercise Physiology
- Altitude Medicine
- Human Physiology
Background:
- Acute mountain sickness (AMS) is a common condition at high altitudes.
- Understanding physiological responses to hypoxia is crucial for managing AMS.
- Intermittent exercise protocols can simulate real-world exposure scenarios.
Purpose of the Study:
- To investigate physiological markers associated with AMS symptoms.
- To examine responses during intermittent walking under normobaric hypoxia.
- To correlate physiological data with AMS symptom scores.
Main Methods:
- Twelve healthy males performed a 125-minute intermittent walking protocol (50% VO2max).
- Participants were exposed to normoxic and two hypoxic conditions (14% O2, 12% O2).
- Physiological variables and AMS symptoms (Lake Louise, ESQ-c) were measured.
Main Results:
- Oxygen saturation, heart rate, core temperature, and perceived exertion increased with hypoxia.
- AMS symptom scores positively correlated with physiological markers like heart rate and body mass changes.
- Significant differences in physiological markers were observed across the three oxygen conditions.
Conclusions:
- Physiological responses are linked to AMS symptoms after short-term hypoxia.
- Markers such as heart rate and thermal sensation can indicate AMS severity.
- This study highlights physiological correlates of AMS in a controlled exercise setting.
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