I have shoulder, neck and upper back pain sometimes. My situation is probably totally different from yours, but here goes. I have a disc issue in my lower neck, an old sports injury. It puts pressure on a nerve that effects my left arm and shoulder. It became so painful, I almost had to stop riding. I went to a chiropractor and he said I needed to change my riding position. When the head is out in front of the shoulders it puts stress on the neck. A normal healthy neck, no problem, but my neck is a problem. I adopted a more upright riding position. I ride with my head over my shoulders. This puts less strain on the neck muscles. Therefore less pain in my arm and shoulder. In addition, I was riding with very bad position. I'm not a trained cyclist. I had my hands wide apart, arms straight with shoulders shrugged. I found out this causes my arms, shoulders and neck to act as a shock absorber, transferring every bump directly to my spine. I now ride with narrow hands, arms bent and low shoulders. This puts almost no weight on my hands and I'm not a human shock absorber any more. I also have no more hand pain or numbness. BTW, numbness in the hands can sometimes be from a problem in the neck, not the hands. Of course the upright riding position is less efficient and I probably ride slower, but I'm old and I was never built for speed anyway. The added benefit of a more upright position is that I can see my surroundings better. For years I rode all hunched over and mostly saw the road 3 feet in front of my wheel.
