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Published on: March 15, 2019
Exercise exacerbates acute mountain sickness at simulated high altitude
R C Roach1, D Maes, D Sandoval
1Division of Physiology, Department of Life Sciences, New Mexico Highlands University, Las Vegas 87701-9000, New Mexico, USA. rroach@hypoxia.net
Journal of Applied Physiology (Bethesda, Md. : 1985)
|February 5, 2000
Summary
Exercise exacerbates acute mountain sickness (AMS) symptoms at high altitude. Physical exertion worsened AMS severity and incidence in early exposure hours, potentially due to reduced oxygen saturation.
Area of Science:
- Physiology
- Altitude Medicine
- Exercise Science
Background:
- Acute mountain sickness (AMS) is a common condition at high altitudes.
- The impact of exercise on early AMS development is not fully understood.
Purpose of the Study:
- To investigate the effect of exercise on the severity and incidence of AMS during the initial hours of high-altitude exposure.
Main Methods:
- Seven men were exposed to simulated high altitude (4,800 m) in a decompression chamber.
- Participants underwent exercise (Ex) or sedentary (Sed) protocols during the first 6 hours of a 10-hour exposure.
- Measurements included AMS scores, ventilation, pulmonary function, oxygen saturation, and fluid balance.
Main Results:
- Exercise significantly increased AMS symptom scores compared to sedentary conditions (4.4 vs. 1.3, P < 0.01).
- Arterial oxygen saturation (Sa(O2)) was lower during exercise bouts (76.3%) than at rest (P < 0.01).
- A slight positive fluid balance was observed during exercise between 3-6 hours (P = 0.06).
Conclusions:
- Exercise intensifies AMS severity and incidence in the early stages of altitude exposure.
- Mechanisms may involve exercise-induced arterial hypoxemia and minor fluid shifts.
- Further research is needed to elucidate the precise contributing factors.
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