Hi Pippin how are things. I remember reading an old RS where Glenn said he played Little League Baseball and was on the wrestling team in high school. When he passed, I remember reading an interview with someone (sorry-can't remember who) who stated he was a really good Basketball player. Sounds like he was just an all around good athlete.
Side Note: I remember him saying in that RS interview that he was also in the Boy Scouts. He quit the piano lessons because it interfered with the baseball and scouts. Sounds like he had a very traditional 50's/60's childhood.