My doctor actually prescribed me a few exercise to strengthen my lower back. He was a older Japanese man I found it quite entertaining. We were in his office he was going through the exercises and he asked if I workout on my own. I said yeah, I do casual running and play basketball. He then told me that I looked ok and to just continue what I was doing.adfnio said:Could it be your posture while riding be the culprit? Or perhaps you could work out the lower back area when you are not riding to strengthen that body part.