It's a great point about most persons in the USA spending so much time indoors and not fully climitazing themselves because of it. I don't believe that I have acclimated myself fully to the heat and humidity because when the weather is really awful like the heat and humidity of the last week I stay indoors most of the time except for a ride. Example was Tuesday, despite all the awful heat I spent 23 hours indoors under cool temps and 1 hour outside biking. Despite the oppresivness of it, that was doable under those circumstances.

I also equate this to extreme low temps in the winter. While we don't fully climatize ourselfs to a life spent in the elements we do get some exposure going to and from our cars and walking in and out of buildings. I know those first below freezing days feel very cold, however after a prolonged cold spell and some sub zero days I don't feel shivery cold going out in 25-30 F temps. so even being an indoor creature, I and I believe most of us, do get somewhat tempered to the climate we are experiencing after a few days or weeks. Of course some folks with asthma and other physical issues experience this different from people who do not have those things to contend with.

Speaking of cold and shivering I think I'll go get a popsicle!