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Supramaximal Intensity Hypoxic Exercise and Vascular Function Assessment in Mice
Published on: March 15, 2019
Sea-level exercise performance following adaptation to hypoxia: a meta-analysis
Darrell L Bonetti1, Will G Hopkins
1Institute of Sport and Recreation Research, School of Sport and Recreation, AUT University, Auckland, New Zealand.
Sports Medicine (Auckland, N.Z.)
|February 11, 2009
Summary
Altitude training enhances endurance performance, with natural live-high, train-low (LHTL) being most effective for elite athletes. Artificial protocols show promise for subelite athletes, with placebo and training camp effects also playing a role.
Area of Science:
- Sport Science
- Exercise Physiology
- Environmental Physiology
Background:
- Altitude training (hypoxic exposure) is increasingly popular among athletes and sport scientists.
- Various protocols exist, including live-high train-high (LHTH), live-high train-low (LHTL), and artificial hypoxia methods.
- Understanding the efficacy of these diverse protocols is crucial for optimizing athletic performance.
Purpose of the Study:
- To conduct the first meta-analytic review on the effects of six different hypoxia adaptation protocols on athletic performance and physiological measures.
- To compare the effectiveness of natural versus artificial hypoxia, and different training/living scenarios (LHTH, LHTL, LLTH).
- To identify potential moderators of protocol effectiveness, such as altitude level and duration of exposure.
Main Methods:
- Meta-analysis of 51 studies evaluating performance (power output) and maximal oxygen uptake (VO2max).
- Random-effect models were used, incorporating covariates for study characteristics.
- Probabilistic inferences were based on a smallest worthwhile effect of 1% for performance enhancement.
Main Results:
- Natural LHTL demonstrated substantial performance enhancement in subelite athletes (4.2%) and possible enhancement in elite athletes (4.0%).
- Artificial brief intermittent LHTL showed very likely enhancement in subelite athletes (2.6%).
- VO2max increases were very likely with LHTH in subelite athletes (4.3%), but a reduction was possible in elite athletes (-1.5%). Placebo, nocebo, and training-camp effects were identified as mediators.
Conclusions:
- Natural LHTL is currently the most effective protocol for enhancing endurance performance in both elite and subelite athletes.
- Certain artificial hypoxia protocols are effective for subelite athletes.
- Future research should focus on modifying protocols to further enhance performance, considering VO2max and psychological effects as key mediators.
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