What do they do?
The difference of Sit Ups and Crunches are major. You're not only working different muscles, but some aren't even used to aid in abdominal shaping.
Sit-Ups, are a movement which require keeping feet flat on a surface while moving the psoas muscle area (lower back and pelvis) to meet yourself at the top of the thighs. By doing this, you're putting un-needed pressure on the psoas muscles and nothing on the abdominals.
Crunches on the other hand, emphasize the moving of the sternum to the pelvis, contracting the abdominals with less range of motion. Instead of using supporting muscles, you're limiting yourself to only using the abs.
Which is better? Neither. They are equally better in their respective ways. If you want to tone most of the lower portion of your upper torso, then use Sit-Ups (though, do them right or else you will injure your lower back) and if you want to shape and strengthen the abs, use Crunches.
I'm not entirely sure. But when you do sit ups, you're flexing your hips. Also, when you're doing crunches your feet come off the ground, and "crunch" the middle part of your body. Crunches are better at toning your abs though. Sorry I can't give you more information :)
There are various exercises referred to as "sit-ups" and as "crunches." In general sit-ups have a longer range of motion and use more muscle groups to complete. Crunches limit movement to the zone where the abdominal muscles are used.
I think crunches are when you sit half way up and sit ups are when you sit nearly fully up.
Fank you you jewish terrorist <3
thank you :)