Whether a popular opinion or not, not many trainers support the idea of doing crunches for ab training. But why are so many experts against crunches? Here are 9 reasons why you should reconsider doing crunches:
1. They can be dangerous.
Sure, if you do them with proper form crunches can be harmless. But most people are not doing them right. Doing crunches in both a safe and effective manner require a good deal of body awareness and anatomical knowledge. It’s far too easy to pull a muscle, slip some disc in your spine, or create more subtle (but unpleasant) problems that won’t show up immediately.
2. They wreak havoc on your spine.
Many instructors will tell you to “flatten” your spine to the floor when doing crunches. This makes sense to some degree because it protects you from major injury. But unfortunately, it also trains your body to stay in that flattened position. The spine has curves for a reason. Any real core training will take into account those curves and find ways to support the spine without having to compromise the natural integrity of its form.
On the other end of the spectrum are those who don’t flatten their spine, but also don’t understand the transverse abdominus and its role in maintaining a neutral spine. These people will often release the spine too much (over extending the curve of the lower back) which results in major issues (and points right back to reason #1).
3. They can create poor posture.
Crunches reinforce bad habits that result in poor posture. Many people unconsciously “tuck their butt under” and “hold in their abs” as a result of too much bad ab training. Again, this reinforces conditioning that disrupts the natural curves of the spinal. The end result to all this “ab strengthened” a really STRONG bad posture.
And since the whole body is connected: Tucked bottoms result in flattened spinal curves which usually bring the shoulders slumped downward, the head forward, and starts to slowly work on that “old lady hump” in the back that nobody wants. You can always tell when someone does too many crunches almost immediately by their posture alone.
4. They over-focus on surface muscles instead of deep core muscles.
Crunches really zone your surface ab muscles. While it’s true that these are your “six pack” muscles, they are not the most important muscles for true core strength. You can have very “strong abs” and still end up with poor core support. If all you care about is how your stomach looks, by all means, keep crunching away. But if you want real strength that supports the body in motion (and is critical for living a pain-free life), go deeper and work your inner abs.