Simply slimming requires aerobic exercise, and sit-ups belong to unarmed muscle training, which mainly stimulates rectus abdominis and has little direct effect on slimming. It is recommended to run for 30-40 minutes with moderate intensity (heartbeat is about 1.5-2 times of normal heartbeat); Or jump rope, do aerobics, etc. The key is to be aerobic, that is, to keep breathing normally during exercise and not to hold your breath, such as sprinting.