Effect of hypoxic "dose" on physiological responses and sea-level performance
Randall L Wilber1, James Stray-Gundersen, Benjamin D Levine
1Athlete Performance Laboratory, United States Olympic Committee, Colorado Springs, CO 80909, USA. randy.wilber@usoc.org
Medicine and Science in Sports and Exercise
|September 7, 2007
Summary
Live high-train low (LH+TL) altitude training requires athletes to live at 2000-2500m for at least 4 weeks, 22 hours daily. This optimizes acclimatization and performance benefits.
Area of Science:
- Sports Science
- Exercise Physiology
- Altitude Training
Background:
- Live high-train low (LH+TL) emerged to overcome limitations of traditional live high-train high (LH+TH) altitude training.
- LH+TL aims to enhance acclimatization via increased erythropoietin (EPO) and erythrocyte volume while enabling high-intensity training at lower altitudes.
- Simulated LH+TL environments (hypoxic tents, nitrogen apartments) offer convenient alternatives to natural altitude exposure.
Purpose of the Study:
- To determine the optimal hypoxic dose for LH+TL to achieve physiological benefits and performance enhancements.
- To answer key questions regarding optimal altitude, duration, and daily exposure time for LH+TL.
Main Methods:
- Extensive review of research conducted by the study group on LH+TL altitude training.
- Analysis of physiological responses to varying altitudes, durations, and daily exposure times in LH+TL protocols.
Main Results:
- Consistent findings indicate specific parameters are crucial for deriving benefits from LH+TL.
- Optimal conditions involve living at a natural elevation of 2000-2500 meters.
- A minimum duration of 4 weeks and daily exposure of at least 22 hours are recommended.
Conclusions:
- The recommended protocol for LH+TL is living at 2000-2500m for over 4 weeks, for over 22 hours per day.
- This regimen facilitates altitude acclimatization, boosts EPO and erythrocyte volume, and supports sea-level performance gains.
- Adherence to these parameters is key for athletes seeking to maximize the benefits of LH+TL altitude training.
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