There are many reasons for leg pain, such as strenuous exercise, followed by other diseases such as trauma, lumbar disc herniation, or arteriosclerosis occlusive disease of the lower extremities. 1. Strenuous exercise: if recent strenuous activities, a large amount of lactic acid in the muscles to produce accumulation, due to lactic acid metabolism needs a certain period of time, so there will be leg pain. 2. Trauma: If the leg is struck or collided by external objects and the local soft tissue is damaged, it will cause pain. Fractures may occur in serious cases, which may also lead to limitation of the patient’s activities. 3. Lumbar disc herniation: Lumbar disc herniation is mainly caused by disc degeneration, injury, heredity and other factors. Typical symptoms are lumbar pain, sciatica, and numbness in the lower limbs. Some patients will have intermittent claudication, and the pain in the lower limbs is obvious, and there will be radiating pain. 4. Other diseases: arteriosclerosis occlusive disease of the lower limbs, knee osteoarthritis, osteoarthritis, bone fracture and other diseases can lead to leg pain. There are more causes of leg pain, if the pain can not be relieved, you should go to the local regular hospital for relevant examination. If the leg pain is caused by trauma, you need to seek medical treatment in time to avoid delaying the condition.