There are two main reasons for tendon pain in the limbs: 1. It is possible that strenuous exercise or lifting and carrying heavy objects, walking with weight, may lead to fatigue in the limbs of the muscles, tendons, ligaments and other soft tissues, after a long time, it is easy to lead to the formation of local strain or strain, so that the local bruising and inflammation is easy to produce, will stimulate the peripheral nerves around, appearing painful sensation. In addition, because the blood circulation is faster during activity, the inflammation and bruises produced are metabolized faster, so the symptoms are not obvious, but after rest and cold, the blood circulation slows down and inflammation builds up, leading to increased symptoms of tendon pain in the limbs; 2. It may be polymyositis, which is an autoimmune disease, that is, the body’s autoimmune system has an immune response to its own tissues, leading to This is an autoimmune disease, which means that the body’s autoimmune system has an immune reaction to its own tissues, leading to an inflammatory state of the muscle tissues, and therefore the symptoms of tendon pain in the limbs will appear.