Crunches (or variations of crunches like bicycles) are synonymous with a flat abdomen. They are the go to exercise for anyone with any ambition of having a flat stomach.
Times have changed since crunches were established as a standard abdominal exercise. We have learnt more about the human body and in particular our spine and how our core and abdomen work. We have been able to see how different conditions (like pregnancy and methods of exercise) impact on our body and we’ve had the time to see the long term outcomes from crunches.
Today there is a growing consensus that relying solely on crunches for core strength, can be harmful to your spine, can be do more harm than good to the post-natal woman’s core recovery or anyone else with Diastasis Rectii and are not effective at training the true core muscles. Here are some reasons I recommend reducing or even stopping crunches:
1. The Effect on The Spine
The crunch position (at the top) puts pressure on the spine while it’s in flexion, which makes it more vulnerable to injury or strain and possibly impact on nerves.
2. Can Cause Back Pain
Our spine is designed to have subtle curves in it naturally – it’s called the neutral spine. Prolonged, repeated, loaded (with body weight) crunching takes the spine out of that neutral position, placing the vertebrae and the discs in between, under stress and strain. Talk to anyone with a pinched nerve or herniated/slipped/bulging disc and they will tell you to steer clear of anything that could cause it.
3. The Benefits of Crunches are Narrow
Crunches are purely enhancing the muscles’ ability to pull the spine into flexion. They do not address the full and deeper core. There is a significant amount of abdominal contents your core is keeping in your abdomen. Your RA, a strip of muscle running down the middle of your abdomen will not, on it’s own, give you a flat stomach. You need your full core to be functionally strong and with some endurance to have a flat stomach.
4. They Will make Diastasis Rectii worse
Anyone with Diastasis Rectii (DR) need to avoid these at all costs if they want any hope of having their DR heal.
5. Can lead to Poor Posture – creating other problems
Crunches can often be done, fast and with feet locked under some weight and often with a tucked pelvis. All of which engages the hip flexors, resulting in them being tighter. This can create hip pain along with problems trigger by a perpetually tucked pelvis.
Crunches do help strength your rectus abdominis. So they do a job, but doing 100’s of crunches won’t get you a flat tummy and can lead to more problems you don’t want. So make them just a SMALL part of your core training.
If you are looking for a deep core muscle workout take a look at my 9 exercises to replace crunches post.