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To crunch or not to crunch and why?

So this has been a bit of a "hot" topic lately, with some trainers suggesting to crunch but most articles say DON'T crunch!

So I wanted to address this today.


Before you get any ideas on not reading the article and going ahead and doing crunches I want to say:

- Full crunches and Full sit-ups are both bad for your Diastasis Recti and your back!

So don't do them!

BUT (and this is where the confusion often occurs)
A small curl-up (or head-lift) correctly engaging ALL your deep core muscles can be beneficial.

DON'T go and rush off to do these now WITHOUT reading the rest of this article, because if they are done incorrectly you will WORSEN your diastasis


A little background

In the past (and some doctors are still living in the past, so be careful) it was thought that crunches were the way to repair diastasis recti.

The is because when you preform a crunch motion the gap between your rectus abdominus muscles actually reduces - i.e. the gap width lessens!

HOWEVER what ultrasounds have now shown is that even though the gap lessens the linea alba (the connective tissue) actually gets distorted.

NOTE it is the linea alba that you want nice and firm to stop your belly hanging out - so distorting it under pressure is not a good thing!

Even head lifts (or a small curl up) does this IF you haven't engaged the deep core (TVAs) correctly - this is why their is often a blanket NO CRUNCHES mentioned in online programs but not when you see a PT.

So lets check out what happens to your Linea Alba when you to a head lift incorrectly versus correctly ....

What is happening inside?

In the first diagram you can see the rectus abdominus at rest with a "lax" linea alba between them.

If we were to press on the gap our fingers would sink down

The second is what happens when a curl-up is preformed WITHOUT engaging the TVAs first. The gap lessens but if we pressed on the gap our fingers would still sink down

The third diagram shows what happens when you ENGAGE your TVAs BEFORE doing the curl up. Note the gap lessened (but not as much as the curl-up on its own) BUT the linea alba is tight - if we pressed on the gap our fingers would not sink down as deeply - This is what we want!

What is happening outside?

So now that we know what is happening on the inside - lets check out what is happening on the outside - where you can see ....

The above images show what happens when you do a curl up WITHOUT engaging your TVAs, see how even though the gap has reduced I can still put my fingers into the gap and pull the muscles apart.

Now lets look at what happens when she engages her TVAs first

These images show what happens when you complete a curl-up after engaging your TVAs - note the gap looks closed, but it is actually because the linea alba is under more tension!

How to correctly do a curl-up

Note, given I (nor a PT) is standing right beside you, I suggest getting someone to watch you carefully doing these, to ensure no doming is happening and to check the firmness of your gap.

If you are not getting the gap firm - go back to the TVA exercises as you are not ready for these.

1) Start on your back (make sure you go down on your side and then roll over to your back), knees bent, feet just less than hip width apart, back in neutral position. Start with your arms by your side.

2) Stay here for a moment practising your breathing. Let your thighs go heavy and feel like they are sinking into your hips.

3) Inhale focusing on your rib cage expanding

4) Exhale and gently engage the deep core system (pelvic floor and TVAs)

5) Check you have engaged correctly - gap should be firm and it should be easy to lift a foot off the ground.

6) on the next exhale, engage the deep core, slowly bring your chin towards your chest, then flex the neck and upper back so they come slightly off the ground NO FURTHER than the top of your shoulder blade (scapulae)

Curl up only as far as a flattened abdomen with adequate linea alba tension can be maintained (no doming, bulging or sagging)

Start with 1 set of 10 (if you can maintain form) and build up to 3 sets of 10

I hope this helps with some of the confusion - please remember these are curl-ups NOT full sit-up OR full crunches where your shoulder blades are coming off the ground.

If this helped you please share this article, and if you have any comments ask them below

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