Maximal Cardiorespiratory Responses to One- and Two-Legged Cycling during Acute and Long-Term Exposure to 4300m,
Abstract
During exposure to high altitude, maximal oxygen consumption (V02max) is diminished immediately in proportion to the reduction in oxygen content of the inspired air. As the exposure lasts beyond a couple of days, there is an increase in arterial oxygen saturation. However, V02max does not increase possibly due to a reduction in cardiac output. The purpose of this investigation was to study the contribution of the increase in oxygen content to the working muscles without the potentially confounded problem of a reduced cardiac output. Seven male subjects (aged 17 to 24 years) performed one- and two-legged V02max tests on a cycle ergometer at sea level (SL), after 1 hour at 4300m simulated altitude (SA) and after two weeks of residence at the summit of Pikes Peak, CO. (PP;4300m). Cardiac output limits maximal performance during two-legged but not one-legged cycling. Since only one-legged V02max increased as more oxygen was made available to the working muscles then the altitude-induced reduction in cardiac output can be implicated as being responsible for the reduction in V02max during two-legged cycling.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 14, 1987
- Accession Number
- ADA185730
Entities
People
- Bruce Ruscio
- Charles S. Fulco
- Laurie Trad
- Paul B. Rock
- Vincent Forte Jr.
Organizations
- United States Army Research Institute of Environmental Medicine