Q: Should I do sit-ups to make my stomach flatter?
A: They won’t help much. There is no way to selectively burn belly fat—“spot reducing” is a myth. In any case, the energy burned by sit-ups (actually not that much) and other short exercise comes almost all from stored carbohydrates, not body fat.
But sit-ups can strengthen abdominal muscles, which in turn provide better support for the back and can improve posture and prevent slouching— and that may make you look trimmer.
In any case, instead of old-fashioned sit-ups, you’re better off doing curl-ups, also called crunches, as follows.
- Lie on the floor with your knees bent, several inches apart, and your feet flat on the floor.
- Contract your abdominal muscles while pressing your lower back into the floor, which will help lift your upper body.
- Come up to no more than a 30° angle, hold for a few seconds, then lower slowly.