Seven Days of Intermittent Altitude Exposures Improve Endurance Performance at 4300 M
Abstract
The purpose of this study was to determine if seven days of intermittent altitude exposures (IAE), in combination with either rest or exercise training could improve endurance performance and induce physiologic adaptations that are consistent with altitude acclimatization at 4300 m. Ten adult lowlanders (26 plus or minus 2 yrs; 77 plus or minus 4 kg; 1 74 plus or minus 3 cm; means plus or minus SE) completed a cycle endurance test. The cycle endurance test consisted of two continuous steady-state exercise bouts (15 min at 40% and 70% altitude-specific peak oxygen uptake (V?02peak)) followed immediately by a time-trial performance test (time to complete a standardized amount of work on a cycle ergometer) during an acute exposure to 4300 m altitude-equivalent (446 mmHg) once before (PreIAE) and once after (PostIAE) 7 d of IAE (4 hod-1, 5 dowk- 1, 4300 m). During each IAE, five subjects performed exercise training (45-60 minod- 1 at 60%-70% of V?02peak) and five subjects rested. Both groups demonstrated similar improvements in time trial performance and physiologic adaptations during rest and steady-state exercise from PreIAE to PostIAE. Thus data from all subjects were combined. Seven days of IAE resulted in 1) a 16% improvement (P<0.05) in time-trial performance from PreIAE (35.3 plus or minus 2.6 min) to PostIAE (29.2 plus or minus 1.9 min) 2) a 4% improvement (P<0.05) in exercise arterial O2 saturation from PreIAE (77 plus or minus 2%) to PostIAE (80 plus or minus 20%), 3) a 15% reduction (P<0.05) in exercise heart rate from PreIAE (136 plus or minus 6 bpm) to PostIAE (116 plus or minus 6 bpm, and 4) a 22% reduction (P<0.05) in exercise rating of perceived exertion from PreIAE (10 plus or minus 1) to PostIAE (8 plus or minus 1).
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 01, 2006
- Accession Number
- ADA449833
Entities
People
- A. Cymerman
- B. A. Beidleman
- C. S. Fulco
- G. S. Skrinar
- Michael N. Sawka
- S. F. Lewis
- S. R. Muza
Organizations
- United States Army Research Institute of Environmental Medicine