Effect of Hypohydration and Altitude Exposure on Aerobic Exercise Performance and Acute Mountain Sickness
Abstract
Hypoxia often causes body water deficits (hypohydration, HYPO); however, the effects of HYPO on aerobic exercise performance and prevalence of acute mountain sickness (AMS) at high altitude (ALT) have not been reported. We hypothesized that 1) HYPO and ALT would each degrade aerobic performance relative to sea level (SL)-euhydrated (EUH) conditions, and combining HYPO and ALT would further degrade performance more than one stressor alone; and 2) HYPO would increase the prevalence and severity of AMS symptoms. Seven lowlander men (25 +/- 7 yr old; 82 +/- 11 kg; mean SD) completed four separate experimental trials. Trials were 1) SL-EUH, 2) SL-HYPO, 3) ALT-EUH, and 4) ALT-HYPO. In HYPO, subjects were dehydrated by 4% of body mass. Subjects maintained hydration status overnight and the following morning entered a hypobaric chamber (at SL or 3,048 m, 27 deg C) where they completed 30 min of submaximal exercise immediately followed by a 30-min performance time trial (TT). AMS was measured with the Environmental Symptoms Questionnaire-Cerebral Score (AMS-C) and the Lake Louise Scoring System (LLS).
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 2010
- Accession Number
- ADA540809
Entities
People
- Beth A. Beidleman
- Charles S. Fulco
- Ingrid V. Sils
- John W Castellani
- Michael N. Sawka
- Robert W. Kenefick
- Samuel N. Cheuvront
- Stephen R. Muza
Organizations
- United States Army Research Institute of Environmental Medicine