When crunches are wasting your time – and what you can do instead
Crunches essentially target one core muscle – the rectus abdominis – by flexing the trunk in what is basically an ‘isolation’ exercise.
The rectus abdominis (RA) is a superficial muscle (known as the 6 pack muscle) – it lies closer to the surface – which is why we can see it – and why most people target it.
Around every joint (including the spine and for the sake of this conversation, the ‘core’), there are inner or deeper muscles, and there are some outer, or superficial muscles. Generally it’s the inner ones that provide stability at a joint. And conversely, generally, it’s the outer ones that most people tend to train…
During pregnancy it’s the deeper muscles of the core and spine (the transverse abdominis and pelvic floor amongst others) that create stability and prevent pain.
When you’re pregnant, and in the early post natal stages, you probably won’t see this 6 pack anyway – and it is not responsible in isolation for any rehab of the stomach after birth – so it’s kind of redundant to train it that way.
Here’s where crunches can make things worse and why-
When you’re pregnant –
The RA attaches to the pubic symphysis – which, if de-stabilised during pregnancy, will cause pelvic girdle pain. Every repetition of a crunch is a contraction of the rectus abdominis – which means it pulls at the pubic symphysis.
This is not what you want when you have a ton of relaxin surging through your body loosening off all of those joints anyway…
For more on pelvic girdle pain you can go here -http://stableandstrong.com.au/life-hacks-avoid-pelvic-girdle-pain/
The RA has a line of tissue running down the centre called the linea alba. This widens and loosens during pregnancy to make room for the baby – in severe cases it’s typically known as abdominal separation or DRAM. A tighter rectus abdominis (which is of course what happens to a muscle if you exercise it) can cause a larger separation and can be harder to rehabilitate post pregnancy.
For more on DRAM you can go here -http://stableandstrong.com.au/dram-diastasis-recti-need-know/
Post pregnancy –
If you have some form of abdominal separation a normal crunch will exacerbate the gap – due to an effect know as ‘coning’. (Details are in the blog post on DRAM linked above)
Working the RA in isolation without the deep abdominal muscles such as the TVA and the pelvic floor can create a strength imbalance – and asymmetry can cause pain and injury.
So if this is you, this means avoiding every form of crunch – low ones, full ones (sit ups), side ones, bicycles – all of it – until the above issues are resolved.
What to do instead – pelvic floor and transverse abdominis activation, then co-ordination, and then finally strengthening.
If you aren’t sure about how to activate the pelvic floor – you can follow this little guide here – http://stableandstrong.com.au/exactly-activate-pelvic-floor-correctly-caution-real-talk-ahead/
It’s not forever – it’s just for now. And once baby is out, DRAM is healed, the pelvis and spine are stable, and you can control your pelvic floor – if you want to – crunch away 😉