You need to tighten your abdomen when skipping rope. When skipping rope, we should not only tighten the abdomen, but also pay attention to tightening all the middle parts of the upper body, preferably tightening the perineum (you can try to tighten the anus when you can't tighten it completely at first). In the process of skipping rope, because the center of gravity of the body constantly vibrates regularly up and down, all internal organs in the human body can be squeezed, pulled and rubbed, which is a benign stimulus to the organs themselves and their surrounding fixed tissues, such as ligaments, omentum, ligaments, diaphragms, nerves and blood vessels. But while getting these benign stimuli, there will also be a downward force under the action of gravity, which will make these organs and tissues produce a drooping tension. With the increase of age, organs will gradually sag. Therefore, in the process of exercise, if there is the force of abdominal contraction, the middle part of the upper body is tightened, which not only has the force of massaging the organs, but also buffers the downward pull of the impact force and gravity on the organs during jumping. At the same time, the tightening of perineum will also increase the strength of perineal muscles. Exercising perineal muscles will increase the strength of perineal muscles, increase the strength of supporting and protecting organs, and alleviate the relaxation of urethral muscles caused by aging and female childbirth.