Let me explain my situation last September I had a race about half way through I went to stand up and felt an awful pain in my hamstring I tried to ride and made it about another 40 or so miles before I could no longer pedal. I took it easy for about 6 months when it started to feel better I started to run again and play other sports it felt great no pain what so ever. I got back on the bike and the pain started again nothing I could not ride through just an uncomfortable pain. The only thing I changed before the injury was shoes I fine it hard to believe that would cause the problem but I could be wrong, I thought about changing the seat height I was wondering if anyone else might have any suggestions.