Alias; Tough guy loses weight and has an abdomen belt.

This is a fitness tool. In fact, sit-ups don't necessarily need this tool.

Sit-ups, a form of exercise. Lie on your back, put your legs together, raise your hand, contract your abdominal muscles, swing your arms forward, and quickly become a sitting position. Keep your upper body bent forward, touch your feet with your hands and bow your head. Then return to the sitting position, and so on.