Preacclimatization - The Future of Mountaineering

Title:
Rapid ascents of Mt Everest: normobaric hypoxic preacclimatization

Background:
Acclimatization to high altitude is time consuming. An expedition to Mt Everest (8848 m) requires roughly 8 weeks. Therefore it seems very attractive to reach the summit within 3 weeks from home, which is currently promised by some expedition tour operators. These rapid ascent expeditions are based on two main components, normobaric hypoxic training (NHT) prior to the expedition and the use of high flow supplemental oxygen (HFSO2). We attempted to assess the relative importance of these two elements.

Results:
So far rapid ascents to Mt Everest have been successful. The participants carried out 8 weeks of NHT, reaching sleeping altitudes = 7100 m and spent at least 300 h in NH. At rest a flow rate of 2 l O₂/min is sufficient to keep the partial pressure of inspired oxygen (PIO₂) close to 50 mm Hg even at the summit. For ativities of ~80% of the maximum rate of oxygen consumption (VO_2max) at the summit 6 l O₂/min are required to maintain a PIO₂ above 50 mm Hg.

Conclusion:
Preacclimatization using normobaric hypoxica (NH) is far more important than the use of HFSO₂. We think that NHT will be widely used in the future. The most effective regimen of preacclimatization in NH, the duration of each session and the optimal FIO₂ are still unclear and require further study.

Full study can be found HERE