They shouldn’t! Too many people complain of a sore spot after some core moves like crunches, butterflies, and roll ups.
There are two reasons ab exercises give you a raspberry on your low back: lack of spinal mobility and lack of abdominal strength.
An exercise is only as effective as your ability to execute it and compensating for lack of either of these skills will just chafe your skin raw. Any “rolling up” kind of exercise should have you feeling like you’re peeling your spine off the floor one joint at a time. To do that, you first have to be able to move your spine.
Second, you’ll need the requisite strength to actually flex your spine in a loaded position. Bringing your legs lower in c-spine exercises to look “fit” without maintaining lumbar flexion is not just poor form, but will come back to haunt you the next time you’re asked to do lat pull-overs to a press up.
We created this simple video to help you learn to control your spine and activate your deep core muscles so you can get the most out of every class and leave walking on air.