How much heat can the Apple Watch Series 6 handle?

I wore my series 6 Nike version the other day in a jacuzzi, then sauna, then steam room without even remembering I had it on my wrist, coincidentally the watch started acting up on its own later that day, starting and changing apps. But it was back to normal functionality on the next day. So was it just coincidence or the Apple Watches are sensitive to a little heat and/or moisture? It would be controversial to have a sports watch that can’t handle sports related environments… what if I want to track a session of hot yoga? Will the Apple Watch survive? I thought since we saw commercials of astronauts wearing it in space I would be fine wearing it in a sauna down on earth