“So this is my question. Can you describe what most pro baseball players wear under their uniforms? I know sliding shorts, a.k.a. spandex compression shorts, are probably popular. But what percentage wear cups? Any commentary on this sportsgear question would definitely be appreciated.”
Well, for me it depends on the day. I know that when I play ball I like to wear compression shorts. Some days, when it's really hot I wear just a jock. What makes that fun is when your team wears white pants at home. I played on a summer team in college where our home uniform had white pants. This guy from a college down south loved it. One day during a rain delay he was talkin by his locker which was right nxt to mine about how his school's team had white pants and they showed off some days for the ladies. If you only wear a jock, it's sometimes pretty noticable. These guys are trying to show off to the girls who are in the stands watching them.
If you go to a minor league game you may see some guys only wearing jocks under their uniforms, you now know why.
I do know that most catchers I have been on teams with will wear a cup along with a spandex kind of short over the jock.
Hope you found this helpful Chris. Keep those questions coming in.