On my ride home yesterday, I concentrated on my posture - bending my back more, weighting my arms less (elbows bent of course), and balancing on my seat. Although I was not without numbness, it may have been a bit better. My bag was particularly heavy and bulky due to some eggplants I was carrying, but I think these adjustments might give me some immediate relief. I will work on my core strenth and address the other variables for the long term benefits.