Arm soreness may be caused by physiological factors such as overwork, excessive exercise, myofasciitis, epicondylitis of the humerus, tendonitis and so on. 1. Physiological factors: if the arm for heavy labor, will lead to arm overwork, or strenuous exercise, will lead to arm muscle lactic acid accumulation, and arm soreness. 2. Myofasciitis: the etiology of myofasciitis is not clear, and it is considered to be caused by long-term repetitive activities or muscle injury. Patients will show persistent soreness and pain in localized muscles, activity limitation and muscle tension. 3. Epicondylitis of the humerus: Epicondylitis of the humerus may be caused by repeated long-term contraction of the anterior wall extensor muscles, and patients will experience pain on the lateral side of the elbow, reduced grip strength and other symptoms. 4. Others: patients with arm pain are also considered to be caused by tendonitis, frozen shoulder, brachial plexus neuritis, cervical and rib deformities. For physiological factors caused by arm pain can not be treated, most will be relieved after rest. If the arm pain persists without relief, you need to consult a doctor to check the cause of the disease and take appropriate measures to treat the cause of the disease.