1, exercise local muscles: lying flat and swinging your legs from side to side can strengthen leg strength, exercise waist muscles, increase muscle strength and improve muscle stalemate.

2, increase the flexibility of the body: lying flat, swinging your legs left and right, can make the waist and back of the leg in a state of tension, can stretch the bones and muscles well, make the body softer, and reduce the symptoms of cramps and joint pain.