Throw The Crunches Out With The Bath Water

The desire to aesthetically improve to our bodies is the most common driving force getting us into the gym. Sure for some it’s more about health or sports conditioning, but even they still yearn for that physically hot body. Now if we break the body down into parts the area most of us want to see improvement in is the mid-section or in gym parlance the abdominals. Nothing else seems to impart the image of health, vitality, fitness, youth and sexiness more than flat stomach or ripped abs.  For men it can be a lack of muffin top, a six pack or a flat abdomen with a strong V muscle (Adonis belt) exposure. For women it’s generally, a flat tummy, a small waist and even better an abdominal vertical line known on social media as the ”ab crack”. 

This desire for the perfect mid-section has led to billions of dollars being spent on lotions, potions, contraptions and pills with mostly unsatisfying results. Add to that crazy diets and even crazier exercises all leaving those concerned feeling cheated and dissatisfied.

For those training mostly for aesthetic reasons know that the only way to gets your abs showing is to get your body fat very low. No matter how good your ab routine unless the sheath of fat covering them goes away you won’t see the abdominals lying below. This means six pack abs require a healthy and maybe, somewhat restrictive diet and high calorie burning exercise. In short running and full body movements will do far more for your lean abdominal look than lots of crunches ever will.

Core Function

To understand how the abdominals should be trained we first need to understand their function. The core muscles of which the abdominals are a part of are there to give support and stability. They do this by preventing extension, flexion, lateral flexion and rotation of the spine when under tension whether you are stationary or in motion preserving posture. For instance when you are carrying a heavy grocery bag in one hand your core muscles keep you upright preventing you from leaning or falling over the heavy bag, this is anti- lateral flexion. Now let’s pick-up a heavy box with both arms and squeeze it up against your abdomen as you walk. The weight will try to pull your torso down and forward. To keep you from collapsing forward at the waist your core engages with anti-flexion force. Lift that same box over your head to put it away on say a high shelf and your core will engage to keep you from bending backwards, this is anti-extension.  

Core Training Disfunctions

So, if you want to strengthen your abdominals why would you use flexion exercises (crunches, sit-ups, reverse crunches) when the core muscles by design are trying to minimize this motion?  Dr. Stuart McGill (considered by many the top spinal mechanics expert) has authored a couple of studies on the dangers of flexion exercises for the spine. In these studies porcine spinal segments were put through repetitive low magnitude flexion and extension forces. The effect would be similar to doing flexion exercises. The results were disc bulges and herniations in the samples.

Let’s take a closer look at the spine. The joints in the spine are not ball and socket like your knee or shoulder they are vertebral bones and flat discs and therefore do not have pivoting motion. The disc itself has a jelly like center that is mostly water called the nucleus pulposus. This is surrounded by the annulus fibrosus, a ring of strong fibrous cartilage that keeps the disc’s integrity. When a crunch is performed the anterior portion of the disc is compressed most. Since the center is mostly fluid it displaces posteriorly placing greater pressure on the posterior portion of the disc. This also leads to a drying out of the disc as fluid is forced out and the disc loses height further narrowing open spaces.  Over time this uneven force can result in a tear in the annulus. If the offending force is continued part of the pulposus will protrude through, this is known as a bulge or herniation.  

Let’s use the watermelon seed example. Take a watermelon seed out of the melon. While still moist place it between your thumbs. Pump your thumbs back and forth as if mimicking a body flexing.  As you do this it gets harder to keep the seed in place and it will slip to one side or even spit out entirely. The compression from flexion exercises has a similar effect on your nucleus pulposus.

If you have a disc herniation, depending on location and severity, you will experience localized pain and radiating pain that can be debilitating if it is impinging on a nerve root. Even if the pain resolves if the disc stress isn’t relieved arthritic changes will eventually occur. 

Functional Core Training

Now that we know what not to do let’s talk about how to train your core. Since your cores primary function is to resist extension, rotation and lateral flexion then using movements that cause these stresses while you resist are ideal. In a standard plank you hold yourself up on your forearms and balls of feet while keeping your body straight. The stress you feel would force you into extension if you allowed it to. So, holding the plank would strengthen the anti-extension muscles. There are many variations of planks that can be found on YouTube. Side planks do the same for lateral flexion. Another series of exercises referred to as Dead bugs (because of your body position) works your core with anti-extension, anti-rotation and anti-lateral flexion movements. All these exercises are designed to strengthen your core while protecting your spine.  

Following these new principles will give you better core support, make you stronger all over and with a healthy diet give you that sexy mid-section you always wanted.

References:

ncbi.nhm.nih.gov – Intervertebral Disc Herniation: Studies on a Porcine Model

ncbi.nhm.nih.gov – Extent of Nucleus Pulposus Migration

Men’s Health.com – Why Crunches and Sit-ups Are Bad for Your Back

Strengthcoachblog.com – Is Doing Abs a Waste of Time

Uwaterloo.ca/applied-health-sciences – He’s Got Our Backs