Step on your stomach to exercise your abdominal muscles? This is ridiculous. Who thought of that? It's dangerous to do so. Abdominal muscle exercise should be obtained through normal physical exercise, such as sit-ups and push-ups. It is impossible to step on it, and it is easy to hurt internal organs, especially the stomach. I advise you not to listen to such nonsense in the future, or it will be too late to regret it! I wish you a happy growth!