Hello, twisting your waist can't reduce your stomach. Waist twisting can only help gastrointestinal peristalsis and promote defecation. When there is less stool in the body, I feel that my stomach has become smaller, but it has not changed. Sit-ups are useless to thin belly. Sit-ups are strength exercises, which will only make your abdominal muscles stronger and stronger, but not reduce abdominal fat. The most effective way is aerobic exercise, such as brisk walking, jogging, cycling, swimming and skipping rope. For more than 30 minutes each time, three or four times a week. You can control your diet during the period, and it will have obvious effects in one or two months.