My upper back has been susceptible for years to get stiff or spasm when I do any sort of weights, typically for a few days. I've been told that totally resting a sore muscle is not ideal, rather very gentle exercises and stretching aids recovery.
What should I do and what should I avoid to keep this muscle group loose and aid recovery without exacerbating it? It's a large muscle used in a whole range of motions so resting totally effectively means not using my upper body at all!
Further, what sort of exercises are recommend after recovery to make it stronger and less prone to this problem?