Doing a standard crunch or sit-up is generally not recommended for postpartum women, especially when we know a diastasis recti or DRA is present. This is because the way a crunch is generally performed has the effect of severely increasing intra abdominal pressure, pushing your organs outwards against or through the gap, and downwards onto the pelvic floor – directions you really don’t want your organs forcefully heading. You can actually see what you’re training your abs to do if you look straight down as you curl up: a cone shape, bread-loaf shape or a pregnant looking belly… these are clear signs of diastasis recti, a core not working right… and not the effect you’re working out to achieve! See animated image >>>


COPYRIGHT MUTU System Limited 2015. Express permission required for reproduction in any form.


And so postpartum exercise specialists and Womens Health Physiotherapists recommend against crunches until the core musculature (including pelvic floor) is fully restored and strong enough to withstand the movement.

BUT… and there is a *but* here… supine spinal flexion (the forward curl-up motion from lying on your back) engages and shortens the rectus abdominis muscle. The rectus is the vertical, ‘six-pack’ abdominal muscle, the exact same superficial abdominal muscle that has separated from its midline connective tissue, and weakened with a diastasis recti. A diastasis compromises all your ab muscles, both laterally as the gap widens from side to side, as well as lengthways along the stretched and weakened rectus. So exercising to shorten it, if performed correctly, is a good thing.

The other *but*, is that spinal flexion (bending forward, whether lying on your back or in any other position) is a perfectly natural human, functional movement. Sometimes, you want or need to curl your body, or bend forward. Not repetitively, or excessively, but you might want to curl all the same.

So if it’s both potentially beneficial in shortening the stretched-out rectus, and its essentially functional, why do we tell you not to do it?

2 main reasons:

  1. Very importantly, because BEFORE you can train the abdominal muscles in this way effectively, you need to have trained the deeper abdominal muscles: the Transverse, the Inferior Obliques and the Exterior Obliques to all work together, along with the muscles of your pelvic floor. This vital phase of mind-to-muscle reconnection, of learning to recruit and engage the right muscles, first in isolation and then as a unit, must come first. That’s what MUTU System does.
  2. And also very importantly, because there’s an awful lot of ways of doing it wrong that will make a diastasis or weak pelvic floor worse, not better. Often a crunch is performed whilst sucking in, or holding your breath, causing your stomach to pooch or bulge out and your organs to bear down on your pelvic floor. Often the hip flexors and lower back are taking most of the strain, and the targeted muscles, the rectus abdominis as well as the deep transverse abdominis muscle, are not recruiting at all, whilst the diastasis gap is widening further.

And so unless a specialist is right there with you to help you gauge whether midline tension of the core musculature is being maintained, and pelvic floor function is controlled and protected, you will do more harm than good. It is preferable and much safer to find alternatives with techniques and patterns which have less potential to harm.

KimVopniAnd talking of specialists… I spent time recently in LA with my great friend and peer Kim Vopni of Pelvienne Wellness where we had been asked to consult for an exercise instructor training company on adapting workouts for pregnancy and postpartum. As we played and experimented with various adapted ‘crunch’ movements, we decided it was time to put this information out there! We both regularly recommend against crunches, when giving general, online advice where careful personal supervision isn’t possible. By the very nature of much of Kim’s work, as well of course as the MUTU System online program and blog, we simply cannot be ‘hands-on’ enough to be sure you’re getting it right and therefore caution prevails.

I also wanted to write this because often a Women’s Health Physiotherapist will specifically prescribe a variation of a curl movement at the appropriate stage of her client’s recovery, and I know (because you regularly write to me about it) that you worry that ‘all crunches are bad’. Be mindful that your therapist or Physio will be carefully monitoring and cue-ing breathing and technique to ensure the right muscles are doing the work and full benefits are being achieved. Your stage of restoration is appropriate, you’re recruiting the right muscles…

…The movement is not a bad movement. You just need to be sure you’re getting it right, and that your body is ready for it.


Well, first of course please know that you must have achieved foundation training for the deeper abdominal muscles before a curl up of any description is going to be effective. Then:

1. Are you able to isolate and engage your core effectively?

Try this from lying on your back with knees bent up and feet flat on the floor. Place your hands on your ‘hip bones’ – the bony corners that jut out at the front of your pelvis on each side). Move your fingers slightly inwards and downwards from there, where its soft. Exhale as you gently draw your abs inwards, whilst engaging your pelvic floor muscles. Imagine you’re drawing a tampon further up inside you. When you engage your TVA and PFM, you will feel a tensing of the broad flat muscle under the pads of your fingers. It should be tensing downwards, towards your body, not bulging, pushing or straining outwards. If your stomach pooches or pushes away, if you’re holding your breath or the movement is forceful, then you’re working the outer abdominal muscles and TVA isn’t doing its thing.

2. Your body’s clear signals you’re doing it wrong

Watch for these danger signs when attempting to engage your core without strain first, then especially when performing any abdominal exercise. If you are experiencing (feeling and/or seeing) any of these symptoms when intra abdominal pressure is increased, you’re not getting it right, and you’re doing more harm than good. Back up. You’re not ready yet.

  • Bulging or doming anywhere on your abdomen when you do any exercise
  • Bulging in or from your vagina or rectum, or any feeling of heaviness or ‘bearing down’
  • Pain – In your back, pelvis, abdomen, hips or leg
  • Leaking urine or faeces when you sneeze, laugh or cough; or leaking as you’re rushing to the toilet

3. Try it!

To perform a curl or crunch, keep the range of movement very small at first. By that I mean don’t lift your head and shoulders very high off the ground – there is no muscular benefit to curling right up anyway. And keep the levers short – so knees bent up, feet flat on the floor.

Straight legs, outstretched arms, raised legs or any adjustment that increases the load, increases the strain and will result in bulging. Inhale fully with your head and shoulders completely relaxed on the floor. Then exhale slowly and focus on gently engaging your abdominal muscles as well as your pelvic floor muscles, as you lift your head and shoulders just off the floor. Relax completely back down on the inhale. Watch for doming, straining and be mindful of how your pelvic floor feels.

Increase intensity one small shift at a time: straighten your legs out a little more, but keep knees still bent and feet flat. Take arms outstretched above your head to increase the lever. Hold a small pilates ball or child’s football in your outstretched arms and squeeze it gently between flat palms as you lift, engage and exhale. Just try one of these changes at a time – each will have a big effect on your ability to maintain tension in the midline of your abdomen.


Diane LeeKim and I ran our thoughts past highly respected renowned Physiotherapist and teacher Diane Lee of Diane Lee & Associates who confirmed: “Absolutely abdominal curls are important! Just not full abdominal sit ups. All the abs are impacted by DRA (Brauman 2009) and need attention. … It’s a wrong message to say never do a curl up! That isn’t life, but we have to teach the curl-up properly and ensure that tension is maintained in the midline. When the belly bulges or the midline domes that is the clue that the deep system is off and the PFM have to work so much harder to resist the increased pressure. So by all means teach abdominal flexion exercises – with a focus on the strategy and not the reps. … always feel for midline tension and abdominal flattening not bulging…”

Diane generously provides a lot more technical detail than I have included above for ease of understanding in the context of this post. If you would like to dig deeper into Diane’s work and listen to full lectures, visit her amazing new Learn With Diane Lee website, full of free resources and video.


I hope this helps clarify a little on the big Crunch Debate! There are no crunches in the MUTU System programs for the simple reason that as mentioned above, until the foundations of core reconnection and muscle recruitment are established, they won’t help! But once that stage has been reached, shortening and strengthening the rectus muscle along its length through carefully supervised increasing ranges of motion, can be both functional and beneficial.

Just make sure you’re doin’ it right 🙂

You might also like:

Your Post Baby Body | Whats Normal + What Isn’t?

How To ‘Engage Your Core’

PostPartum Exercise | When Are You Ready?

Enjoy control and confidence in how your body looks, works, and feels. No more embarrassing leaks or discomfort. You deserve better and you can have it with MUTU System - the medically endorsed 12 week online recovery program for mothers.