Arm pain can be caused by the following factors: 1. The most common factor is orthopedic surgery, such as excessive exercise or over-exercise leading to muscle strain, or shoulder spondylitis, cervical spondylosis, shoulder joint function damage, etc. 2. When excessive exercise is performed the day before, the anaerobic glycolysis pathway is activated, releasing a large amount of ATP and accumulating a large amount of lactic acid in the body. When too much lactic acid is accumulated in the body, arm aches and pains will occur. 3. arm aches and pains will also occur when rhabdomyolysis is caused by incorrect exercise methods. 4. arm aches and pains will also occur when heat cramps, heat exhaustion and pyrexia occur. 5. arm aches and pains will occur in acute cerebrovascular diseases, such as cerebral hemorrhage, cerebral infarction and cerebrovascular stroke.