Running calf pain, considering the lack of exercise, but also can not be ruled out is caused by periostitis, lumbar disc herniation and other reasons, should be timely consultation to identify the cause. 1. Lack of exercise: If you usually lack exercise or exercise less, when you suddenly carry out strenuous exercise such as running, there will be too much lactic acid accumulation in the muscles of the calf area, which will lead to a localized inflammatory reaction and result in pain. It can be manifested as running calf soreness, which can be relieved when resting. For this type of situation, it is recommended to stretch the limbs before running. After running, you can apply local heat or massage to relieve muscle pain. 2. Osteochondritis Dissecans: Osteochondritis Dissecans is more common in adolescents during the growth and development period, and these patients are prone to inflammation of the periosteum of the calf due to rapid growth and activity. It can be manifested as obvious pain in the calf when running. 3. Lumbar disc herniation: if the patient has lumbar disc herniation, the pressure of lumbar disc increases when running, and the aggravation of lumbar disc herniation stimulates the nerves, leading to muscle pain or radiating pain in the innervated area, which can be manifested as running calf pain. It is recommended to clarify the degree and direction of the herniated disc, and then choose the appropriate treatment plan according to the condition. Running calf soreness may also be caused by injuries to leg muscles and soft tissues. If physiological causes are ruled out, timely consultation should be made to ask the doctor to clarify the specific causes, and appropriate treatment should be carried out if necessary.