This literal proposal is impractical for virtually anyone as it requires living in a particular place all the time, but as others have pointed out, some simulat

This literal proposal is impractical for virtually anyone as it requires living in a particular place all the time, but as others have pointed out, some simulation of this technique is extremely common. Sleeping in an artificial low pressure room or hyperbaric chamber is most common, but even the high-altitude camps are not just limited to truly elite athletes. We did this even in high school. My cross-country team was pretty good (we won two California state championships in four years) but still just high schoolers. The school was in Los Angeles but we spent two weeks at the end of every summer before fall semester started camping in the San Bernardino mountains doing two-a-days, usually doing a complete lap around Big Bear lake in the morning and then a shorter, faster run in the afternoon. But it's funny you mention it because I remember the guy who won the individual state championship my freshman year and took second overall in an open 5k I vaguely remember running right before the season started was a student at Rim of the World high school, which is located in Lake Arrowhead and he actually did live at high altitude.