Should I be embarrassed to take my shirt off in public?

You could always wear long yellow socks, walk funny and pretend you're a chicken.

I answered jokingly on some other threads you started, not now though - but it's a question of the place and the culture of the place - if you are walking in downtown Manhattan financial district, that could be 'poor form'. If you are running around your already warm neighborhood, trying to get to a mile or four, no big deal, at least in the neighborhoods I've lived in.

I'm a used-to-be-shy person, probably still have some of that, but I philosophically got over a lot of that when I was about seventeen (long story I've told before, but in short, when I went to work at a hospital at sixteen, I caught on that everything wasn't about me and started being more interested in others. It was gradual).