I have been riding for years. some years I ride more and better than others. I am not in really good riding shape right now. I ride better in the fall and winter months because my kids are in school and I get to ride during the week. My neck and shoulders are hurting and getting stiff on rides longer than 30 miles. For me, it is conditioning. During the fall and winter months you should work on upper body weight training. Some light weights for the arms and strengthening like pilates helps. When you start riding alot in the spring and summer, you can cut back or stop it all together. New riders, particularly in a group, will ride stiff armed and have their shoulders in their ears. I always remind riders to smile when they ride. It is almost impossible to keep your shoulders up and tight when you are smiling! Try it. Relax your arms - they need to be bent at the elbows. Change your arm position on the bike when you get tired - from the bar drops to the handlebars, etc. When you ride, you should be working from the waist down. You should not be moving your upper body or pulling with your arms. Hope this helps!