The common causes of arm pain in summer are blowing air conditioning, exertion, cervical spondylosis, heart disease and so on. 1. Blowing air conditioning: less clothes in summer, if suddenly from the hot place to the air conditioning air-conditioning heavy place, may be due to blowing air conditioning lead to local muscle vasoconstriction, nerve irritation, etc., causing arm pain. 2. Exhaustion: After playing ball games and other strenuous exercise, arm pain may be caused by exhaustion, which can usually be relieved after rest. 3. Cervical spondylosis: Cervical disc herniation, cervical spondylolisthesis and other diseases can lead to arm pain, numbness, impaired limb movement and other symptoms if they compress the nerves. 4. Heart disease: Heart disease can lead to shoulder pain radiating to the arm, which may also be accompanied by chest tightness, arm numbness and other symptoms. Arm pain can also be caused by other reasons, once the arm pain is severe or can not be relieved should go to the hospital in a timely manner to identify the cause and targeted treatment.