- I thought the reason that it’s been recommended to do crunches with both the hips & the knees flexed at 90deg while lying on your back was to avoid using the psoas instead of the abs, which could lead to hyperlordosis, so I’m a bit puzzled by your suggestion of doing crunches over an exercise ball with legs extended.
- You say crunches are like sitting & slumping into your waist, but crunches work against gravity whereas slumping is passive – or have I misunderstood what you meant?
- I know crunches aren’t particularly functional, but don’t we use the abs in this way when going from lying to sitting and won’t toning the abs like this enable them to work better when used functionally?
Any clarification on any of these points welcomed!