The first method, if the arm muscles are sore because of sudden exercise or how to increase the amount of exercise, then do more warm-up exercises before exercise for future relief, and then do some gentle stretching exercises after exercise, which can generally eliminate the pain in a few days. The second method, if sleeping or sitting for a long time causes arm muscle pain, you should first adjust your sleeping position and sitting position, and then get up every hour to shake your hands and do a stretching exercise for five to ten minutes. The third method, if you hurt your arm because of exercise or other reasons, you'd better do a slight massage and apply a hot towel to relieve the pain. The fourth method, sometimes if it is muscle pain or other physical discomfort caused by a cold, take some anti-inflammatory drugs or painkillers. The fifth method, if you often have arm pain and shoulder and neck discomfort during the day and night, may be caused by spine or scapulohumeral periarthritis. It is best to go to the hospital for professional massage, acupuncture and medication.