I can be very competitive, and have played lots of sports. If a player outmaneuvers me, strikes me out, tackles me, etc, I take it very personally. I paint a mental bullseye on their back for the rest of the game. I usually keep my cool though and use that shame to motivate me. However, if I keep messing up, and everyone is screaming at me, and criticizing me, I have been known to break down and cry. It is humiliating, especially in upper level men's athletics, in front of people you know. I can't look my teammates in the eyes for weeks afterwards. I don't do it as much as I did when I was little though, but I can only be pushed so far.
I also sometimes can't bring myself to beat people under certain circumstances. A trite example:
When I was little I would play basketball against my dad. He seemed like an invincible giant, and he would never let me win. That was okay, there's no shame losing to him, I thought. As the years passed, he sustained numerous injuries and wear-and-tear due to age, sports, and years of manual labour. Every year the games grew closer, and soon went from a dad fooling around with his kid, to an intense competition. He still won every time though, and he would smile and say something like: "I still got it", or "I'm not ready for a wheelchair yet, buddy", etc. I was 16 when I realized my dad is three inches shorter than me and is in his mid-50s. I was very aware of the fact that I could finally beat him, but I just didn't have the heart. I had remembered when age and a shoulder injury had knocked him out of his men's hardball league. I remember watching him come back from the injury and try to pitch, and he was absolutely murdered. He kept coming back, every game and kept getting annihilated. People started making fun of him and yelling taunts about him being impotent and washed up. Then they cut him from the team. It took him a long time to admit it, but he eventually admitted he was no longer able to compete at that level. It crushed him. And so, to this day I can't bring myself to beat him in sports. Maybe that's cowardly, but I just can't.