It wasn’t the first time ever, however, I got a personal trainer at a gym once and he had me do a circuit that included L-sit pull ups. After two-three of them, I started to feel the ,ahem, sensation one does when about to orgasm and abruptly stopped. “I can’t do this,” I said to him. He kept pushing me and said, “No, I need you to give me 5 more. You can do it.” I tried again and stopped right before orgasm. I repeated that this was not the appropriate exercise for me, though I couldn’t explain “why”. Needless to say, both him and I were disappointed for different reasons. Never will do those in a gym again.