1) Are sit-ups a better exercise than crunches? Because it feels like sit-ups are extended crunches.
2) Aren't sit-ups an abs-exercise? Because I just did 80 sit ups (and 20 crunches) and even though I expected my abs to hurt, my back aches instead.
Yes set Ups are abs exercise .. Crunches work on the 2 uper muscles .. And set ups work on the 4 upper muscles !
Does your back is a little bet bent over !?
What exercise is good for the muscles of the belly button area?
If you do a full sit up you engage the hip flexers as well(iliopsoas muscles) which have attachments into the spine as well causing your back extensors to engage, when doing a full sit up. To limit back pain either do crunches or strengthen the low back as well.