I have been playing bass for a few years now but I am starting to begin some more technical and advanced pieces. However, I have been largely hindered by cramps in my bowing hand. I try to concentrate on keeping my bow hand loose, but it doesn't always work, and I need to focus on the harder musical pieces. Is there anyway to stretch or condition my hand so that I don't cramp up so easily (besides playing more)? The cramp is usually between my thumb and first finger and on the bottom side of hand near the pinkie.