Russians wear a wool hat to regulate heat loss through the head in a sauna that is 180F into the 200F's and wet. They wear a big furry wrap when it is blistering cold, ski masks, etc. I read an article once about how that works, which has been lost.
I keep plenty of hair to insulate, but the insulation is wearing out and thinning in time. I have a hat with a shady brim that doesn't catch the wind so much. In a tent when it is cold it makes an exceptional obvious difference to sleep with a head covering. That is a mummy bag effect. I have a down hood that seals around my face, so it doesn't come off in my sleep.
What's a guy to do, migrate to suitable weather, or live next to a fire pit?
Hot surfaces literally burn feet. I had to take care of a 90 year old who had little feeling left in his feet. He had been out in the back yard which was mostly red brick watering and puttering on one of those common Tucson days when you can literally fry and egg on the sidewalk. He couldn't tell that he was burning without looking. The burns were so bad he was receiving home healthcare stuck sitting on his butt. Very ugly deep burn, frequent dressing protract. On the other hand, it doesn't take but a few feet of strolling across hot sand to win that argument.
I can spend and even enjoy a windless cold time nude, but with shoes. I can feel the cold stuff running up my body barefoot. I try to keep the feet from touching ground for more that a sec. which keeps the rest active and so warmer. A body learns. A body knows.
Eskimos have all of those names for different kinds of snow and ice. My feet tell me the difference, too. Snow is often more comfortable to walk on that frozen concrete, or rock, then it can have its effect changed from how much slush is happening. Solid and liquid water change temperature at different rates.
Oops, just woke up from a late night, I'm rambling.
Jbee