Answer: Lie on the floor, straighten your arms and legs as far as possible, and then tilt your ends: lift your upper body with your chest, lift your lower body from the cross (broken back), and lift the root of your thigh off the ground. The higher the sides, the better, that is, the more arched your body is, the better your health is. This exercise can be done in three groups every day, 20 in each group, and controlled in the air for at least 3 seconds at a time. Note: 1. When breaking the span, straighten your toes as far as possible, and use your toes to drive your legs to stretch (instead of using the strength of your thighs, which will make your legs thicker and thicker), so that your body will become a solid whole. At first, your legs may be separated, because it is easier to control, but you should gradually close your legs, and it is best to turn your legs from span to toe and turn your upper body shoulders (that is, your shoulder blades should be buckled back as much as possible and your cervical vertebrae should sink as much as possible) .3. Most people find it difficult to keep their legs "completely" straight. You can let others observe your paint. When the leg is really straight, there will be a depression in the middle of the knee. Only in this way can we really control our legs at two points (two-point alignment principle) and exert the strength of our waist, back, abdomen and buttocks. This exercise exercises abdominal muscles well.

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