With the exception of the beach and (maybe) sunbathing in the park.
I'm an athlete (using the definition broadly) and mix with a lot of athletes, so the men in this context are in pretty good shape. I still think they should keep their shirts on and not e.g. run in the street with their shirts off!
I can't say why exactly, except that I don't like it, even when they're nice to look at 😂