I normally don't post in quick succession, but I wanted to let you all know that this happened! My O2 saturation levels have improved to the point that I'm only using my portable when I walk outside (to/from campus and for exercise). However, I've been very frustrated that I can't do anything more strenuous than walking. Being a runner and athlete is a core part of my identity. From the time I began running in spring 1989 until the day before I landed in the ICU last summer, the only times I didn't do 4-6 days/week of intense cardio were a trip to Morocco in 2000 and 2 trips to Ghana in the 2010s. I ran 25-30 miles/week for 6 months in San Salvador in 1993, at a time when the only other people I saw running were male football/soccer players. During my 8 months in rural El Salvador in 2001, running involved doing figure-8's around 2 soccer fields with long grass hand-cut with machetes. At one end were a horse or cow or two, pigs, chickens, a pack of stray dogs--...