Lying on a flat bed (hard bed), your hands are naturally placed at your sides. After the legs are naturally straightened, tighten the abdomen, lift the legs and squeeze the lower abdomen. When you fall, your legs don't fall to the ground. Continue to repeat the action.

2. Belly rolling (four groups, each group 10-20 times)

Lie flat on the bed, put your hands gently by your ears, bend your legs naturally, lift your upper back, press your lower back against the bed board, and press your upper abdomen hard, but still fall to the ground. Each movement shrinks at the peak 1-2 seconds and slows down.

3. Cycling (four groups, 20 times in each group)

Bend your hands to support the bed board, keep your hips close to the ground, tilt your body at an angle to the ground, look straight ahead, and slightly retract your chin. Imagine a pedal in the air, stepping on it alternately. Each action is 1-2 seconds, so slow down.

4. Bend down and lift your knees (four groups, 20 times in each group)

Support the bed surface with your hands and feet, bend your body slightly, put your knees close to your chest and squeeze your abdomen. This action can speed up and burn fat.

5. From both ends and one side (four groups, 20 times on each side)

Tighten the core, the legs and arms exert force to the opposite side at the same time, and keep 1 second when hitting the ball, so as to tighten the whole abdomen. The whole process will keep the back from the ground, and it is useless to finish it with strength. This action is more difficult than starting from both ends, so adapt first and increase the number of times. If the action is not in place, reduce the number of times.