How can I get my back to stop hurting?
Over the summer, I play tennis every day. When I changed my serve upon a coach's recommendation, my back started to hurt. I had a solid week of pain whenever I served and an additional week of pain at least once a day during serving. The problem went away for a while, but now it is at the point where even though I only have practice once a week, I come out of it with a sore back and shoulders that hurt for days. I'm not quite sure what's wrong or how to fix it. I would prefer not to visit a chiropractor.