The Truth About Sit-ups Post Baby

Are crunches and sit-ups safe post-baby? 

One of the most common questions I get from postpartum clients is, when is it okay to do sit-ups and crunches again post baby?

The recommendations have evolved over the years.

The dated recommendation: Crunches and sit-ups are officially off the table after having a baby because the spinal flexion puts too much tension on the midline (linea alba), which can worsen diastasis.

Sounds legit, right? 

Well, it may be the case for some, but the truth is, we are all unique when it comes to how pregnancy and birth leaves our bodies.

We will all experience some degree of diastasis during and after pregnancy.  This stretching of the midline is how we make room for our growing uterus.

Diastasis comes in a variety of degrees of severity, and what’s more important than how many fingers you can fit between the two sides of your rectus abdominus (6 pack muscles), is how much tension can you generate with the deeper core muscles.  In other words, regardless of the size of the gap, is your core functional? 

One of the best words I like to use when it comes to helping people understand their core post birth, is CONTAINMENT. 

Can you find containment? Can you hold your mid-section together by engaging the right muscles, and therefore preventing unnecessary strain or pressure on your abdominal wall? 

What are the things that put strain on your abdominal wall? Straining, gravity, and, you guessed it, core flexion! 

So I understand why this basic movement has been demonized.

The fact of the matter is, that core flexion is something that you will likely have to perform in life.

So what’s better than trying to avoid it at all costs? Learning how to perform it with a contained core, so that you’re protecting your abdominal wall from being pulled further apart.

The next question is, how the heck do we do that? 

The first step is to learn how to properly engage (and release) your pelvic floor.  

There are many mental cues that may work for you like “imagine picking up a blueberry with your vagina” or “drinking a milkshake” or “move your pelvic floor like a jellyfish” 

These are all great, but the best way to really figure out if you’re using your deep core and pelvic floor properly, is to get a pelvic physio assessment.  They are the only ones who can do an internal assessment and confirm whether or not you are properly engaging and releasing.

Once you have that connection down, you can start to play with different movements to challenge your core. 

The Core Challenge Progressions

Can you find a connection to your deep core muscles when you’re…

1. lying on your back

2. in a side plank position

3. in a front plank position

4. performing other movements (i.e. squats, lunges, deadlifts, push-ups, pull-ups)

5. going into core flexion (crunches and sit-ups)

Why that order? 

We want to go from the least amount of challenge on your core, to the most.

Although they may not be the toughest movements on the list, the crunch and sit up are the toughest movements to perform in conjunction with a contained core.  

Who shouldn’t be doing crunches or sit-ups? 

1. People who are pregnant, or early in their postpartum recovery.

2. People who don’t have a functional core (can’t connect to the pelvic floor, see doming when you challenge your core) *doming is the puffing up of your midline when you challenge your core, indicating that your deep core is not contained/engaged properly, putting pressure on your midline.

3. People with kyphosis (extreme rounding of the upper back).

More on kyphosis or “mom posture”

The one thing I don’t love about doing core flexion repetitively, even if your core can handle it, is that you are repeating a rounded back posture over and over again for x number of reps.  

As moms, we are CONSTANTLY in a rounded back position as we hold and feed babies.

In my humble opinion, there are many other core exercises that don’t perpetuate a rounded back, and so crunches and sit-ups will never be a large part of my own personal training, or of what I prescribe in my classes and coaching.  It’s just not a priority for postpartum fitness on a large scale.

Everything is a core exercise

Once you come to realize that every exercise is a core exercise, then you’re really winning.

Even a bicep curl, when performed correctly, requires you to stabilize your core.  If you don’t, you’ll end up leaning into your lower back to curl the weight (picture the dude in the gym throwing his whole body into it to lift way more than his poor little bicep can handle), and eventually hurt your back doing so.

Whether you’re doing a push-up, pull-up, squat, lunge or deadlift – proper form is heavily reliant on a stable core.  All the isolated core work is great, but if you have a well rounded training program and your form is on point, then your core will ALWAYS get a good workout. 

Why is a stable core so important anyway? 

 Your spine is broken up into 5 parts (cervical, thoracic, lumbar, sacral, and coccyx).

The part where your core is located is around your lumbar spine.  The lumbar spine is unique in that it doesn’t have another bone structure that helps to stabilize it.  Your thoracic spine (upper back) is supported by the rib cage, and the areas below the lumbar spine (sacrum and coccyx) are supported by your pelvis.  

The lumbar spine has nothing to rely on aside from the muscles that fill your midsection.  From your deepest core to your rectus abdominus, those muscles have to engage properly to keep your lumbar spine healthy and happy and free of pain.  

This is why the low back is such a common pain point. An unstable core is an unstable lower back, which is recipe for disaster. 

So in order to keep your back happy, continue to work on your core stability.

What are some good core stability exercises to include? 

1. Dynamic dead bugs

2. Hovering knee variations

3. Plank Variations

4. Side plank variations

5. Horizontal press

The verdict on crunches and sit-ups

So, are crunches and sit-ups inherently evil? No.

Are they a movement that should be avoided at all costs after having a baby? Not necessarily.

Can they be performed properly and without causing harm after having a baby? Absolutely!

Do they need to make their way into your regular exercise routine? Not likely.

Do your due diligence to ensure that your core is functional.  Ensure that you can perform core flexion without causing harm or pain, and use these exercises as you see fit to challenge your core muscles in different ranges of motion.

Last but not least

Do not.. I repeat.. DO NOT do cruches or sit-ups with the intention or idea that it will help you “burn belly fat”.  It most certainly will not, and if you’d like to read more on that myth, check out my post on fat loss and why spot reduction doesn’t work.