Abdominal crunches and its effectiveness?

[dk2108]

Check out this article by Mike Boyle... top US coach. He mentions Dr. Stuart McGills research that shows that repeated flexion (in a lab setting) can lead to disk damage and is in no way functional. He explains how to train the anterior core (which includes abs) properly. All of his articles are well worth checking out if you are into sports performance, rehab, or training of any kind
TMUSCLE.com | Anterior Core Training=

[JeffK]

I found this thread while searching for info re abs crunches & lower back pain. I’m not sure if it’s answered that, but it has raised some other interesting questions (mostly in response to physiobob’s post):

1. 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.
   
2. 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?
   
3. 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!


The issue I originally wanted help with was:

I do oblique crunches most mornings lying on my back with both my hips & knees flexed at 90deg & my calves/feet resting on my sofa. I find this works the abs quite well, but often find that the mid/lower part of my back begins to ache well before my abs. It doesn’t feel like the sort of ache caused by working a muscle hard, it feels more like there’s something not right & that I might be causing myself problems. I’ve tried statically contracting my abs (as in core stability exercises) before starting the crunches & it seems to help, but not all the time.

Any advice/comments, anyone?

TIA, Jeff

[Immortal25]

1. 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.
   
2. 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?
   
3. 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!

You have good points there which was in my mind as well and therefore I welcome this discussion in this thread. Perhaps some brainstorming would be good for all of us fellow physios and what-not.

Ginger, you're righ, they are my own thoughts as I've been trying to find out how to isolate and work out the muscles in the most efficient way possible. Unlike the other muscles in the limbs which can be isolated easily and worked on, the abs are a tough bunch which I'm so interested to experiment on.