Your question is vague. What purpose and effect do you want to achieve? If you lose weight, aerobic exercise will be better, and aerobic exercise will take 30 minutes to be effective. It is recommended to exercise for 30 minutes to an hour. Moreover, losing weight and fat is a systemic reduction and will not be reduced locally. It's just that the human abdomen is the most prone to fat accumulation. If the amount of exercise and time reach a certain level, the abdominal tuck machine will also have a certain effect. However, I suggest that comprehensive exercise has obvious effects, such as jogging, skipping rope, swimming and ball games.