Where the root of the thigh meets the hip is the hip joint, which is made up of the hip bone, femoral head, and the surrounding ligaments, muscles, and joint capsule. The main causes of hip pain include excessive exercise, synovitis of the hip joint or necrosis of the femoral head. It can be relieved and treated by resting, medication and surgery. 1. Excessive exercise: When doing high-intensity exercise such as running, the large amount of lactic acid produced will lead to muscle soreness. Due to excessive exercise, it will lead to muscle spasm in the hip. Generally, no treatment is needed, and the soreness will gradually subside after the lactic acid is eliminated through sufficient rest. 2. Hip synovitis: Hip pain may be caused by synovitis. The main manifestations of synovitis are hip pain and limited movement. Patients should seek medical treatment and follow the doctor’s instructions for medication and other treatments, using anti-inflammatory and analgesic drugs such as diclofenac ethylenediamine latex. 3. Necrosis of femoral head: aseptic necrosis of femoral head can lead to hip pain, especially after walking for a long time, the pain symptoms can be aggravated, and should consult a doctor in time, take conservative treatment or surgical treatment, most of the surgical treatment takes artificial hip replacement. In addition, hip pain after running may also be due to hip labral injury, hip impingement syndrome, sciatic or ulnar impingement and other diseases. It is recommended that patients who have pain in the bone connecting the thigh root and the hip should consult a doctor in time, take a film to check and determine the cause of the disease, and then follow the doctor’s instructions to carry out medication, physical therapy and other treatments.