White Belt Fitness

Crunching

This is kind of a bonus chapter nestled between the deadbug and the bridge, because it comes from a similar place. I really just wanted to take a moment to discuss the idea of ‘crunching’ and ‘sit-ups’ because I get asked about them frequently enough, yet don’t use them or recommend them much in my training. At least I don’t use them in their pure form, on your back, with a load that is so light, it can’t yield a significant benefit.

These two exercises are pervasive in the fitness industry, arguably because they are easy to do anywhere and feeling a burn in your mid-section must mean you’re doing something right. However, burning isn’t really a useful biofeedback tool for training, other than it indicates that your body is no longer capable of producing energy at a rate that exceeds the rate it can clear waste products.

As indicated in the principles of training you want to:

A) Do no harm.

B) Emphasize good movement.

It’s not that crunching or sit ups are inherently bad for you or that you should never do crunches ever. I don’t want to strike the fear of god into you or anything. Consider that many people will:

  • Do plenty of crunching-like-movements getting off the floor or out of bed over the course of their lifetime, so programming more doesn’t make a lot of sense
  • Sit in a posture that is essentially a seated crunch position for up to eight hours a day already, why encourage that posture?
  • Are almost always fairly strong in this area, with reasonable endurance
  • Rarely experience dysfunctional control of the superficial abdominal muscles these attempt to train
  • Use them excessively, flexing the spine more than they need to obtain the training effect they are actually looking for and might end up accelerating an injury mechanism
  • Use really ineffective types of trunk flexion movements like low threshold crunches or situps in great repetition, instead of far more useful but advanced forms of trunk flexion in the context of crunching that minimize exposure/risk

After you do, I think you have a solid argument against using most forms of crunching in your exercise programming at all. Worst of all people will choose types that yield little benefit for the cost.

One of my absolute favourite exercises, The Turkish Get Up (or just ‘Get Up’), involves essentially a loaded crunch/roll onto your elbow and hand, but when done properly really minimizes the amount of spinal flexion. It’s not really appropriate for white belt trainees, who don’t have the right training foundation just yet. It’s also extremely challenging, so people don’t crank out hundreds of them at a time, they rarely do more than a few at a time. Most of the workouts I design with them, have fewer than twenty-four repetitions in a workout and are far more effective overall than doing hundreds of crunches or sit-ups at the end of your workouts.

The main reason I want to discuss training the crunch and sit up, is because I want to save you a lot of training time. I’m a big believer in using training methodologies that yield the biggest bang for buck and most sit ups or crunch variations are not that useful unless you’re a gymnast or olympic diver. If you’re going to crunch, my argument, is use the most effective and repetition limiting versions in a progressive fashion. If you don’t need much use for that movement, as most people do not, then you could skip it almost altogether.

Research by Stuart McGill, someone whose work I’ll reference often, did research that gave us a clear indication that the average spine has only so many bends in it’s lifetime before a herniation eventually results. For those of you who might not know, there are soft jelly-like discs between each of your spine segments, or vertebrae. Hence the expression, ‘I blew a disc.’ These jelly like structures absorb force and can break down with overuse, kind of like a jelly donut if you sat on it or pushed it down with your hand. That’s called a disc herniation, and over time the jelly will typically reset and heal in about six months, sometimes rehab is enough, but not always, and sometimes surgery is required. Many times this herniation creates pressure on a nerve, and that can lead to pain, but not always.

I tell you this, not to freak you out, but to inform you. Actually other research also shows us that simply having that knowledge might make you prone to the nocebo effect, or the opposite of the placebo effect. In this case, it could lead to the belief that you have back pain, therefore you might have a hernia. It doesn’t always work like that. Don’t worry, if you have back pain, you might not have a herniation and vice versa, just because you don’t have pain, doesn’t mean you don’t have a hernia. Remember that pain is a funny thing. Pain and damage are not always the same, though they can be sometimes.

It’s important to understand that the number of bends any spine has is likely different. However, because we know there is a limit at some point, why not use more effective training modalities to minimize risk all the same? You’re going to bend, twist and rotate your spine plenty inadvertently throughout the course of your life, so why bother training it so deliberately and with so many repetitions?

How Strong Do You Really Need to Be?

Arguably, if you can do two or three sets of fifteen to twenty clean reps of the McGill Crunch, you’ve probably hit the baseline requirement for spine flexion strength. More of this exercise won’t yield six pack abs on its own, nor will it spot reduce belly fat, so you probably don’t need to train your six pack muscle (rectus abdominis) much beyond this. It’s a baseline or benchmark, THAT’S IT. So you can check your ability with this exercise periodically to see where you’re at.

Below is the starting position of the McGill Crunch.

StartingPosition.McGill.SitUp

You’re not going to be significantly better of with any other crunching movement, if you can do a few solid sets of these and have good control of the many other torso training exercises in this book. Actually a study by the US army a while back showed that planks improved crunch performance, while crunching did not improve plank performance. If you can get as good a training effect using less risky methods, why not? After a couple of sets of fifteen to twenty of this movement, you’ve established that the muscles being targeted are strong enough and will not really benefit any further from more body weight crunching. It’s like anything else in this book, if the load doesn’t match ability, you won’t get the desired training effect. There are more advanced forms of trunk flexion that could be useful for some people, they just won’t be mentioned in this book.

The finish position is seen below.

FinishPosition.McGill.SitUp

Notice the extremely small range of motion? Actually if Stuart McGill were critiquing me, he might even say, I moved my head a little too much. Using this method, minimizes any bending of the spine, and emphasizes pulling the ribs towards the pelvis, without those ribs or pelvis having to move significantly. More movement is driven by thoracic spine, rather than the lumbar spine (the five lower vertebrae), which arguably deals with bending and rotation a little better than the lower spine.

The single bent knee (as opposed to bending both knees) lowers the total involvement of the hip flexors. Unfortunately other variations tend to overtrain the hip flexors, which is another reason not to do much of them in your training. If you do need to train the hip flexors, there are better methods. With this version you get more actual stress on the muscle rectus abdominis, otherwise known as your six-pack muscle. That muscle pulls the rib cage to the pelvis, but the full crunch or sit-up does so much more than that, making the excessive movement largely wasted effort. This variation keeps the effort far more concentrated to a specific area.

Notice that my hands are tucked into my low back, you could use a towel that was a couple of centimetres thick or about 3/4″ thick. This is for a very good reason, as it allows you to compress your spine into your hands and reduce stress on the low spine. That compression protects the spine better than a normal crunch would, minimizing its overall movement. The hands give you proprioceptive feedback about where your spine is and for proper crunching movements, we don’t want your low spine to lose it’s natural inward curve or lordosis. Regular crunching usually results in the low spine flattening out, which is less than ideal if you go back to our neutral spine concept. The hands prevent that from happening, keeping the emphasis on the abdominal muscles rather than your low back or hip flexor muscles.

If you did crunches without that internal compression you’d reduce the support your muscles can provide your spine in the movement. We have two support mechanisms, ‘passive’ and ‘active.’ Passive support mechanisms are structures like the ligaments that connect your spinal segments and your discs. You cannot contract them to increase their ability to resist force. Active support mechanisms are structures that can contract to improve resistance to a load, things like your muscles and to a little extent some other connective tissues like fascia. You can train these structures to improve that tolerance over time too, so as you get stronger, you increase your ability to resist more force. That’s why people have to work up to a Get Up and can’t just start with it on day one.

If your active structures are properly engaged, it reduces the amount of force the passive structures have to resist, making them less likely to breakdown. If you think back to that jelly donut, if you apply a little bit of pressure with your fingers, the jelly isn’t going to squirt out all over the place and you won’t deform the passive support structures of the fried cake around it. Active support structures keep the pressure low and manageable like that, preventing it from being seriously squished.

Whenever possible, particularly when we have some kind of increase in load, we want to have active structures engaged as best we can to minimize risk. This applies to all of the exercises in this program, it’s why I encourage you to use some of these diagnostic tools before you really test yourself with load. Crunches, can actually place a lot more stress on the spine than people realize, as much as a few thousand newtons of force on a small area like a few discs in your low back.

This is an effect I liken to walking on a bed of nails. If you don’t know how walking on nails is possible, it’s actually really easy to do because of basic physics. If you have a weight, say the weight of a person and you step on one nail, all of that weight is fixated to a single point, so you have a great deal of weight dispersed onto a small area, and you get a significant increase in pressure. It’s incredibly likely that if you step on one nail, your weight is enough, that the pressure will be high enough to penetrate your skin. It might even going all the way through your if the nail is sharp enough. That sharpness decreases the surface area, increasing the force to a small area.

When you spread that force out onto a bed of nails, your weight is dispersed onto more surface area. As long as your weight matches the density of those nails, the pressure will never be enough to penetrate your skin, or even cause discomfort to the pressure receptors under your skin so even sharp nails never penetrate the skin.

If you do an exercise like a crunch, where a great deal of force is put on a small area of the spine, you increase the potential that the force could exceed the ability of those structures to resist that amount of pressure. As opposed to spreading a similar force out over the entire spine as you’ll find in a plank variation or a deadlift.

That’s why I generally prefer torso training exercises like the deadbug, the bridge, or a plank variation. You get more force dispersed over a larger area, minimizing risk. At least with this variation, you get a similar effect, keeping risk low.

Try it, you might be surprised at how difficult it can actually feel. If you can do fifteen for a few sets, you’re strong enough, and you need something that is more challenging, so move onto some more challenging planks or keep an eye out for the blue belt program.

Unless your sport requires a lot of spinal movement, like dance, gymnastics, diving, figure skating or some martial arts, you probably don’t need to train your spine with much, if any actual bending. Ultimately this version is all most people need.

The Exception

I generally try to avoid hard rules about training but in teaching it is often easier to take a harder stance at first and introduce grey areas as a person progresses in ability. You will see more advanced ways of training spinal flexion in future books and realize that they compete with the idea that training spinal flexion is mostly useless.

Not all spinal flexion is necessarily useless and like most things is context dependent. While I typically don’t encourage many, if any, of my clients to do much crunching. I will make an exception for people who display a great deal of excessive anterior pelvic tilt and trouble coordinating glute function (which pulls the back of the pelvis back and down) with anterior abdominal function. The anterior abdominals, trained via a crunching movement, pull the front of the pelvis up and back, making is a synergist with the glutes. The rectus abdominis, along with the glutes and the external obliques and few other muscle contribute significantly to the movement of the pelvis into a more neutral position if you’ve got a ton of water spilling out the front of your pelvis on a regular basis. See the chapter on posture.

For people who display this excessive posture the McGill Crunch is still my preferred complimentary exercise approach, along with bridging and other glute strengthening exercises. However, sometimes they need something a little more aggressive, so we use the Reverse Crunch:

Reverse Crunch Start (KB Supported) Reverse Crunch Finish (KB Supported)

It is my general feeling that unlike a more traditional crunch, where more pressure is placed on the discs of the lumbar spine. This move is a little less risky because the pressure is placed on the more flexible and seemingly tolerant thoracic spine. By tipping the pelvis back into a posterior tilt I’m essentially training an anteriorly tilted pelvis back to homeostasis and a more neutral position. Increasing the strength and tone of the muscles that provide a counterbalance to an potentially excessive tilt brought on by an imbalance.

Sometimes there are more things going on that will need to be addressed other than just using one exercise, but this is a good basic example of a corrective exercise. That is an exercise that provides a corrective balance to what might be deemed a potential problem.

If you have an excessive tilt somewhere, then providing a stimulus in the opposite direction in your training provides better joint centration. Joint centration is positioning the joint to sit more naturally in the center or middle of where active movement might take it. So if you can tilt your hips backward twenty degrees from where they tend to sit naturally, but can only tilt them five degrees forward, that might provide a clue as to how well a joint is centrated. Sometimes a joint shouldn’t be perfectly centered, because the body is not exactly symmetrical. Certain sports often require less symmetry and centration from an athlete for optimal performance. In other instances gender is an influence, for instance women will tend to have a few degrees more tilt forward than backward. Other times is just a lack of motor control. It’s just a place to start.

Here’s an alternative from a bench position:

Reverse Crunch Start (From Bench) Reverse Crunch Finish (From Bench)

The idea is to take your knees to your elbow and use something like a kettlebell or a bench to provide a little additional support for leverage. Do so slowly and controlled, and again there really shouldn’t be a need to exceed two or three sets of fifteen to twenty repetitions on this. Adding that to the routine of someone with an excessive anterior pelvic tilt that isn’t a structural issue, should start to yield a noticeable change in four to twelve weeks, or you’re missing something.

I recommend only utilizing this move if you’re fairly certain you’ve got too much curvature in your low back, or your hips are tilted way too far forward.

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Crunching

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Darren Beattie

Coach, Writer and Founder of Fitnack and Skill Based Fitness. I'm going to change how you think about fitness and coaching. Quality of Life Crusader. Knowledge Junkie. Recovering perfectionist.

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