Thanks Ken, I don't want to sound stupid and this may have been covered somewhere else, but I haven't seen it. Does the higher heart rate have anything to do with getting a light headache (or more) at altitude? Also, I was thinking that if your body is concerned about bringing itself back down to a normal level (possible start of survival mode), does it stop sending oxygen to your stomach, thus possible nausea?
You can tell by my questions that I wasn't a rocket scientist at Chemistry, and thus became an artist. But the subject of why you start acquiring symptoms is interesting. It great you are here to answer some of the "dumber" questions, especially from me.

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