1, sit-ups, sit-ups are the most classic way to train abdominal muscles. Gymnasts are required to lie flat with their legs slightly bowed, get up to a certain extent and then lie down, and then increase the number of times according to their physical strength.

2. Air bike. The exerciser lies flat on the floor with his lower back horizontally attached to the ground. Put your hands on one side of your head and open your arms. Climb on the bike slowly after lifting your legs. The amount of training depends on your physical strength.

3. Use both hands and feet. The exerciser lies flat on the floor with his lower back horizontally attached to the ground. Keep your arms straight, legs straight, and then bend your abdomen at the same time. So that your hands touch your feet, the amount of training depends on your physical strength.

4, fitness ball roll belly. In the gym, choose high-quality fitness balls. The exerciser lies flat on the fitness ball, with his feet on the ground, his hands on his head and his arms open. Your feet are separated by a certain distance to keep your balance.