cthia wrote:The human body is a magnificent piece of excellence within a very frail level of tolerance.
There are many humans who can't go from, say, a low sea level to, say, Denver. Mile High stadium gets so many college footballers cut it isn't funny. They simply cannot breathe. The human body doesn't have nanites or smart paint to adjust back and forth.
I have found that the human body is very adaptable. I grew up in California and did product transfers to Singapore.
Everybody got sick their first trip over there due to being in an air condition environment of 68 degrees with humidity control and then walking through 90 degree outside temperature and nearly 100% humidity and then back to 68 degrees all in the matter of minutes to go from one product line to another. Nobody ever got sick on their 2nd trip. Needless to say, we were always teasing first timers.
Also when I retired I went from Singapore at sea level to 8,500 feet. The first couple of weeks were horrible. I was always tired and needed supplemental oxygen after any heavy activity, fortunately canned oxygen is very common for stores to carry it in the Rockies. After a month or so, I adapted.
Now I can travel from sea level to about 9,000 feet with very little time needed to adapt.
I have no reason to believe I am any different from any other person, heck I am even overweight, which probably does not help.