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https://www.go2altitude.com/mountaineering.php
https://www.sciencedirect.com/science/article/pii/S2095254615000836
https://www.livescience.com/32750-why-do-athletes-train-at-high-altitudes.html
https://www.outsideonline.com/1926461/top-10-towns-high-altitude-running/
https://altolab-usa.com/pages/the-history-of-altitude-training-iht
https://whatsnewinfitness.com.au/altitude-training-history-professor-chris-mclellan