Knee pain after running can be taken to stand and stretch the quadriceps, stretching the hips, heel sliding, side-lying turn the knee and other ways to stretch to help relieve the pain, but do not overstretch, need to measure the strength. 1. Standing quadriceps stretching: standing position, one side of the knee bent backward, one hand grasps the palm of the foot upward lifting, 30 seconds each time, alternating between left and right, to help relieve the pain behind the knee. 2. Stretching the buttocks: lying position with hands crossed behind the thighs, knees bent, slowly stretch to the abdomen, 30 seconds each time, alternating left and right. 3. Heel slide: lying position, one side of the knee bent hook foot, slide along the ground, and then stretch, help to reduce the quadriceps muscle soreness. 4. Side-lying knee turn: side-lying position, legs bent and together, regular lift the upper knee, then together knees. If the symptoms of knee pain after running continue to be unrelieved, you should consult a doctor in a timely manner to clarify the cause of the disease and treat it under the guidance of the doctor.