The danger of strenuous exercise after a meal is obvious, because immediately after eating a meal for strenuous exercise, the flow of blood to the whole body bone and muscle will increase, so that the blood of the stomach and internal organs will be relatively decline, easy to cause indigestion, affect the absorption, and even the seriousness of the cause of chronic indigestion. Therefore, it is not advisable to do strenuous exercise after meals. Running is an aerobic exercise, at least 20 minutes of continuous exercise will have an effect, but generally in order to have a more pronounced effect, the requirement of 30-40 minutes. Special attention, running requires uniform speed, the middle can not stop, try to make the pace, breathing, arm coordination, the process requires relaxation. Before running, you can simply press your legs and move your shoulders, waist, knees, wrists, ankles and other joints. After running, pay attention to do relaxation training, generally can stretch ligaments, pat legs and so on.