Symptoms of muscle strain are mainly localized pain and swelling, and muscle strain at the joints will also show short-term impaired mobility. 1. Pain: muscle strain injury will cause local inflammatory reaction due to the damage of muscle fiber bundles, and then stimulate the nerve endings to occur pain. The pain is usually relieved after rest. 2. Swelling: after muscle strain injury, inflammatory exudation will occur due to the local aseptic inflammatory reaction, resulting in edema of muscles and other tissues, and enlargement of local tissues. 3. Activity disorders: the muscles near the joints are most vulnerable to excessive joint activity, resulting in muscle strain, strain early in the process will cause joint activity disorders due to pain, swelling and other symptoms, such as extension and flexion dysfunction, joint range of motion becomes smaller. If muscle strain is caused by long-term high-load activities or work, strenuous exercise, etc., it is recommended that local braking and rest to enable the recovery of the strained muscles, to avoid untimely rest and aggravation of the strain resulting in structural damage to the muscles. In addition, if the symptoms of muscle strain are significant, it is recommended to consult the hospital and receive appropriate treatment.