The Importance of Spinal Flexion and How To Achieve It

Eric Cressey recently wrote an interesting post titled, "Down on Lumbar Flexion in Strength Training Programs?  Enter The Reverse Crunch."  In it, he explains why he is okay with going into, and training, some lumbar flexion.  His point was that a large percentage of the population is stuck in an anterior tilt with an exaggerated lumbar curve (overly extended).  Therefore, when these people perform a reverse crunch properly, they are flexing their lumbar spine, but not to end-range.  They are flexing from a hyperlordotic position to a more neutral position.  The purpose of the exercise for these people is to strengthen the muscles that will help posteriorly tilt their pelvis (such as the external obliques) and put them into a good lower back position.

While I mostly agree with Eric's post, I do want to discuss why giving people a reverse crunch to help correct their overly lordotic low back position may not always be a good idea.  The reason is because some people stuck in this position are unable to flex their lumbar spine.  In fact, at IFAST we see quite a few clients who are unable to do this.

One of the tools we use in our assessment at IFAST to determine this is a standing toe touch.  An ideal toe touch pattern would demonstrate a reversal of the lumbar curve, which would give the appearance of a flat, lower spine.  As stated above, you will sometimes see a client who is not able to flex their lumbar spine, which is problematic (I am not going to get into it here why you should be able to flex your lumbar spine.  If interested, check out Charlie Weingroff’s Core Pendulum Theory).

Below is a client (I will call him Jon) who is unable to flex his lumbar spine.  When I have him touch his toes, his lumbar curve does not reverse and flatten - it remains extended (check out the pic below).

 

Do you think Jon will be able to perform a reverse crunch properly in a way that will bring his pelvis to neutral?  Most likely not because when he goes to posteriorly tilt he will not be able to segmentally flex his back because he is unable to.  My guess is that he will attempt to flex and get motion at a higher (more superior) segment.   

Therefore, for clients like Jon, it is important to gain segmental flexion first before trying to train the external obliques through lumbar flexion with exercises like a reverse crunch.

One of the mobilization drills I use at IFAST to help gain mobility at the low back (or any segment of the spine) involves breathing into the locked-up segment(s) of the spine.  There are a couple of ways you can do this.  One way to do it by yourself is by laying over a foam roller (or some other relatively hard object) on your stomach.  The position of the foam roller underneath the stomach will depend on where you are trying to mobilize the spine, which I will explain in a moment.  After you are stretched out over the foam roller, try to take several deep, diaphragmatic breaths.  Since the foam roller is blocking your stomach from expanding, the air should travel posteriorly.  If done properly, you should feel like you are breathing into your back and there should be movement in your spine.  If the air is going too high (superior) into your back, then move the foam roller slightly inferior and vice versa.  Finally, it is important to try and relax over the foam roller.  Below is a video demonstrating this.  Sorry for the poor camera angle-you cannot really see the breath mobilizing my spine, but it shows you how to get into position.

 

After performing the above exercise, you can follow it up with something like a rock back into lumbar flexion.  Normally, when performing a rock back you want to stop rocking back when you lose your neutral spine position.  However, in this case, we want the person to get some lumbar flexion (not end-range flexion, just back to neutral).  If the person is getting good segmental flexion with the rock back then I would take him or her to a strengthening exercise for the external obliques (just like you always want to follow up a mobility drill with an activation exercise).  My preferred choice would be Wall Press Abs - making sure the client is in, and stays in, a neutral spine position (so slightly flexed from their normal hyper-lordotic position), however, you could also use a reverse crunch, but be careful that you are not flexing too much.

 
If, on the other hand, the client is still unable to segmentally flex their spine during a rock back and/or breathe into the locked up segment(s) make sure to look at their soft-tissue restrictions.  If the person has been stuck in an anterior tilt position for a long time then they most likely have soft-tissue adaptations that will need to be addressed first.

Hope that helps!  Have a great week everyone!  Oh, and Happy Labor Day!!