1, lie on your back, keep your legs together and straight, bend your hands and hold the back of your head. Lift the upper body with the strength of the waist and abdomen, and be careful not to leave the bed for about 10 seconds below the buttocks. Repeat 20 times.

2, lie flat, legs together straight, hands naturally placed on both sides of the body, tighten the waist and abdomen. Straighten your legs together and lift them slowly. This action can effectively exercise the abdominal muscles and make the abdomen firmer. Repeat 15-20 times.

3. Lie on your back, keep your legs straight and close together, bend your hands and hold the back of your head. Using the strength of the waist and abdomen, slowly lift the upper body and twist the upper body to the left at the same time, and repeat it 20 times in turn.