After thirty five plus years of training including left knee surgery, right shoulder surgery, a torn left bicep, and a herniated disc between my L4 & L5 vertebra, I definitely err on the side of caution when it comes to exercise selection. All strength training movements come with a degree of risk, however some are clearly more potentially dangerous than others.
This is especially true when it comes to core training. The core actually involves a group of muscles that encircle the body in a 360 degree fashion. When the average gym member uses the term, they’re more likely referring to their “six pack” or “abs”. For sake of simplicity, let’s agree that the core includes all the muscles that encircle your midsection and low back.
My purpose in this post is to offer some practical guidelines for some of the most effective and safe exercises to train the core while protecting your spine. The world is full of example of practices that people hold on to because that’s they way they’ve always done them. I hate this argument as a basis for doing anything. What if the way you’ve always done something is wrong?
A large portion of gym members still rely on flexion, lateral flexion, and rotational based movements which is quite the opposite of what the brightest minds in the world of fitness are teaching. Ever hear the phase “What you don’t know can hurt you”? Well, when it comes to core training, it really is true.
What are the four primary movement patterns that can herniate a spinal disc?
Not sure? Okay how about these?
What is your ratio of flexion verses anti-extension based exercises?
What is your ratio of lateral flexion verses anti-lateral flexion based exercises?
What is your ratio of rotational verses anti-rotational based exercises?
If you’re not sure or worse yet, have no idea what I’m referring to, please read this posts in its entirety as the information I’m sharing could literally save you from long-term injury to your spine.
Let’s start with the first question regarding herniating a spinal disc. I tell my clients that their discs are like jelly-filled doughnuts. Every time you move your spine out of neutral, you’re putting stress on your discs. Your spine including your vertebrae and discs is extremely resilient and will stand up under a ton of pressure, however, there is a breaking point and that’s called a herniated or ruptured disc.
A great analogy is to consider a basic wire coat hanger. You can bend it back and forth a few times and it will take the stress with little damage. However repeating this pattern over and over will lead to the hanger eventually breaking. This is how your spine functions. It allows for natural movement so that your body can do all the amazing things it does. However the spine will only take so many repetitions of moving out of neutral before it will “break”.
So to answer my question, the four primary movements that can herniate a disc are excessive flexion, lateral flexion, extension, and rotation. In layman’s terms this means, sit up variations, side bends, machine based loaded back extensions, and machine based loaded rotational exercises. If these movements make up the bulk of your core training, you’re subjecting your spine to a high degree of risk.
If these are the primary exercises you’re doing and I’m suggesting that you do something else, what might these exercises be? In concept, most people focus on training their abs by specifically moving their spine. This as I’ve explained is potentially very dangerous over a period of time.
Note the following by Michael Boyle who is one of the foremost experts on the planet in strength and conditioning, functional training, and general fitness:
“The abdominal muscles by design are stabilizers, not movers. Even if these muscles were movers, ask yourself how many sports or sporting activities involve flexion and extension of the trunk. The answer, if you really know sport, is very few”
“Functional anatomy has determined that the primary purpose of the core musculature is the prevention of motion”
“Instead of seeing the muscles as trunk flexors and lateral flexors and prescribing exercises such as crunches and side bends, I now see them as anti-extensors and anti-lateral flexors and more importantly can now envision a concept that has come to be called anti-rotation. Core training is really about motion prevention, not motion creation”
Note also the following from Dr. Shirley Sahrmann FAPTA, PhD, PT Professor of Physical Therapy/ Neurology/ Cell Biology and Physiology at Washington University School of Medicine, St. Louis, Missouri.
“A large percentage of low back problems occur because the abdominal muscles are not maintaining tight control over the rotation between the pelvis and the spine at the L5-S1 level. The lumber range of motion that many personal trainers and coaches have attempted to create may not even be desirable and is in fact potentially injurious”
“The overall range of lumber rotation is approximately 13 degrees. The rotation between each segment from T10 to L5 is 2 degrees. The greatest rotational range is between the L5 and S1, which is 5 degrees. The thoracic spine, not the lumbar spine should be the site of the greatest amount of rotation of the trunk. When a person practices rotational exercises, they should be instructed to think about the motion occurring in the area of the chest”
“Rotation of the lumber spine is more dangerous than beneficial and rotation of the pelvis and lower extremities to one side while the trunk remains stable or is rotated to the other side is particularly dangerous”
That last quote should put the final nail in the coffin of flexion and rotational based core training.
Hopefully now you will be open to the idea that the safest and most effective way to train the core is to keep your spine stable while moving your arms and legs. This can include simple body weight exercises and also utilize cables, dumbbells, med balls, battle ropes, and ect.
The following are some of the most common exercises I witness people doing that are potentially injurious along with some safer and more effective alternatives:
Stop These: Basic Sit Ups; Roman Chair Sit Ups; Leg Raises; and Glute Ham Sit Ups
The biggest problem with all these movements is that they’re primarily hip-flexor exercises with very little emphasis on the “abs”. If you’re standing up straight and you raise up one knee, that’s hip flexion. One of your most powerful hip flexors is the Psoas which ties off of your T12-L4 vertebrae, and runs down into the legs.
Any sit up variation and especially where your feet are anchored is engaging the psoas to a high degree which again is tied to the lumber spine. The hanging leg raise is also a common exercise and yet it places far more emphasis on the hip flexors rather than targeting your abs. Further, repeated reps of these exercises can be a recipe for disaster for the lower back in the long term.
Do These: Plank; Ball Plank; Ball Plank w/ Arm Motion; Stir the Pot; Body Saw; Jack Knife; Step Off; Ab Wheel; and TRX Fallout
All of these alternative movements can be classified as anti-extensors and are based on keeping the spine stable with movement coming from the arms and legs. They can be very challenging and yet safe. The only exception regarding hip flexion is the Jack Knife. While it does involve hip flexion, the spine stays neutral and the pressure on the low back is very minimal. The Jack Knife is essentially a plank with leg motion and instability added and it really is a great exercise.
Stop These: Side Bends; and Hyper-Extension Side Bends
If sit ups are considered forward flexion, a side bend is simply lateral flexion.
Your spine moves in multiple directions and excessive bending in any direction can ultimately do damage.
Do These: Side Plank; Suit Case Carry; and Waiter Carry
In the class of anti-lateral flexors, the Side Plank is a valid exercise however I seldom use it because it can be uncomfortable and rather boring. I would much rather have even a relative newbie doing Suite Case Carries. They’re basically a walking side plank working the same muscles with the addition of a nice conditioning effect that really will spike your heart rate. If you push yourself to the point that you’re challenging your grip with some decent weight, you might be surprised at how difficult these can be.
Stop These: Rotational Abs
This hits home particularly hard with me because of my past with the game of Golf. I started playing at 11 and actually spent the first few years after college as a club teaching professional. In 2008, when an MRI showed my herniated disc, the doctor said something had to go…golf or weights. As much as I still love the game, I gave it up to save my back. Rotational stress will wreck your back and I think my herniated disc was far more a result of literally thousands of swings over many years of playing verses the work I did in the gym.
Do These: Cable Chops; and Paloff Press
In the class of anti-rotators, these are fantastic exercises that challenge the core around a stable and neutral spine. You can do either exercise both standing and kneeling with the ability to create lots of variety based on the position of the pulley.
Stop These: Back Extension Machine
The problem with this machine is the amount of load it places on the lumbar spine. Muscles are designed to work in units and the low back is meant to function together along with the glutes and hamstrings. These machines really do a great job of isolating the lower back and that’s the problem. Your lower back was not designed to handle extreme loads in the absence of the glutes and hamstrings. Quite simply, there are much safer options.
Do These: Bird Dog; Single Stiff Leg; Kettlebell Swing, and Reverse Hypers
I’ve been using these exercises with my clients for years with no issues. All maintain a neutral spine with the low back, glutes, and hamstrings all working together.
Do These: Bonus – Metcon Exercises
The following are exercises I use primarily for the metabolic conditioning effect however they all challenge the core to a high degree. For a demanding core conditioning routine, combine a handful of the latter core exercises with the following in a giant 10 exercise circuit and have fun.
Keep your reps around 15-20 for the core and metcon exercises where counting reps is appropriate. Then shoot for a hard 45-60 seconds for the timed metcon exercises. A couple of rounds of this type of program will leave you with little need to do any “traditional machine based cardio” because you will be pretty much done.
Med Ball Slams
Closing thoughts for my readers:
I saved this for last because I see it so often in the gym and wanted to make a special point. Go back and re-read the quotes from Michael Boyle and Dr. Shirley Sahrmann from above regarding the inherent danger in rotating your lower body back and forth around a fixed upper body.
You will often see people stretching their low backs in the precise manner Boyle and Sahrmann are speaking out against. I’ve heard people argue that it feels so good to stretch their lower back and that may be true, however that doesn’t make it beneficial or safe. Scratching an itch may feel good in the moment but repeating it for a period of time will eventually draw blood. Ouch!
The lower back simply wasn’t designed for a high degree of mobility. To borrow again from Boyle and his sports analogy, athletes producing high levels of force like a baseball pitcher for example are doing so with little movement in the low back. Power in this case comes from driving the legs in contrast to the rotation of the upper body…all centered around a stable core.