Practical 'Core' Training: Anti-Movements and Dynamic Stability
If you walked into a gym up to the early 2000s, you’d probably see people spending a lot of time doing sit-ups. Maybe crunches, maybe some other version of bringing your knees and chest closer together in the hopes of flattening their bellies or maybe chiseling away at an elusive 6-pack.
Sit-ups eventually fell out of favor, largely due to the influence of Stuart McGill and Shirley Sahrman. Even if you haven’t heard those two names, it’s probably their work that influences most fitness industry beliefs about training the core. McGill is still one of the most cited and respected names in strength training and back health. He posited that repetitive spinal flexion is associated with lower back injuries over time. Sahrman, possibly the most influential physical therapist of all time, taught that the role of muscles around the spine is to largely act as stabilizers and not prime movers.
Starting in the 2000s, endless sit-ups and crunches gave way to endless planks. The plank became the 'gold standard' of core training, for better or for worse. For people trying to get into shape, learning how to hold a plank or plank variation is often the gateway to other forms of exercise.
To this day, there is still a lot of debate about 'core' training and whether or not 'core' is even a useful term. Many trainers roll their eyes when they read the word 'core,' but it's wormed its way into popular parlance, and most people will have a shared idea of what we’re talking about.
Some trainers prefer talking about the 'trunk,' which is fine too. For our purposes, let’s say we’re talking about muscles that affect the spine. This is pretty vague, but it gets us away from just thinking about the rectus abdominis or 6-pack muscles, and gets us away from just thinking about spinal flexion.
Why is this helpful? Because our cores do a lot more than just showcase aesthetically pleasing muscles. We need our cores to help generate, transfer, and absorb kinetic energy. Think jumping, landing, running, swinging, throwing, crawling, basically any practical movement that allows you to interact with the world around you.
Power Generation: Think about swinging a sledgehammer, throwing a punch, using a shovel, or flinging a bag of dog food onto your shoulder. All these movements require rotation, stability, and explosive muscle coordination in order to get the job done. A strong, capable core is essential for all the above movements.
Energy Transfer: Think about the largest muscles in your body: glutes, hamstrings, quadriceps. We think of these as leg muscles, but all those groups also cross over into the pelvis. These are the motors of our body and they produce the most kinetic energy for things like running, jumping, and lifting heavy objects. But they also need a stable 'transducer' to transport that useful energy along a kinetic chain. Think about shooting a basketball from half court; that energy is produced in the legs and hips but is then transferred through your spine out towards your shoulders, arms, and hands. It's the core-to-extremity, summation of forces that allows us to create ballistic power. A strong core is necessary to transfer that energy without losing it due to floppy and unstable joints.
Energy Absorption: This is related to energy transfer, but in the opposite direction. Whenever you receive a jolt of kinetic energy, maybe from landing, getting tackled, falling, or catching something heavy, your core muscles help keep your spine organized and prevent injury. This is also related to the concept of dynamic stability, which in this context refers to how your muscles react to unexpected bumps and jostles that could cause injury if your body doesn’t create stability in the wrong places. Think about carrying something heavy and then accidentally stepping into a pothole; how would your joints handle novel stress?
Now that we have a basic idea of what the spine/trunk/core can do, let’s think about how to train it effectively. We need to think three-dimensionally and dynamically in order to define a practical set of heuristics for core training. Think about all the planes your body moves through (Sagittal, frontal, rotational, and combinations of all three). Your spine and, therefore, your core muscles should be trained along those perimeters, which means:
Spinal Flexion: Usually, people will think of lumbar flexion, but it could also include thoracic flexion. This is the classic crunch movement. Contracting your spine anteriorly, creating a hollow or banana shape.
Spinal Extension: Again, most people will think about the lumbar spine. Arching the back, contracting the posterior chain. Think of the Superman position.
Rotation: Usually, we want this to happen mostly through the thoracic spine, up around the shoulder blades. Any sort of powerful rotation movements like swinging an axe, a baseball bat, or a golf club. Twisting.
Lateral Flexion: Bending toward either your left or right side. Imagine leaning to one side to scratch your thigh or maybe pick up a suitcase.
I’d argue that it’s probably also worth exposing your spine to some compression as well. There are benefits associated with just bearing heavy weights straight down the axis of your spine in moderate doses.
So now we know the basic movements of the spine and what positions they're associated with. Does that mean we should start doing hundreds of repetitions of spinal flexion, extension, rotation, and side bends? I’m sure exposing your core to a full range of movement and stimulation is important, but mindless repetitions of crunches, side bends, supermans, and thoracic twists probably aren’t optimal for most people.
The safest and most effective way to train the core is probably through anti-movement. What is anti-movement? It’s simply teaching your core to resist external forces from various angles. Anti-movements are generally isometric, meaning muscle tension is created but very little movement is visible.
Think of a plank. You contract your anterior core to prevent your lumbar spine from flopping out into extension. When in a plank position, gravity and the weight of your own body create forces that compel your spine to give up and relax into lumbar extension. By contracting your muscles, you can resist those forces and maintain a neutral spine.
That’s all anti-movements are, using your muscles to resist forces and try to maintain a neutral spine. Instead of thinking about the movement you’re trying to create, think about the movement you’re resisting.
Anti-Extension: Using your muscles associated with spinal flexion to resist going into extension. Movements include planks, hollow body and dead bugs, ab wheels, and inchworms.
Anti-Flexion: Using your muscles associated with spinal extension to resist going into flexion. Movements include deadlift variations and many movements that use anterior loading.
Anti-Rotation: Using your muscles associated with opposite-side rotation to resist rotating with the external force. Many one-armed plank variations, one-armed pulling movements, Pallof presses, and rotational landmine movements can train anti-rotation.
Anti-Lateral Flexion: Using your muscles associated with bending to the opposite side to resist side bending under external force. Side planks and unilateral carries are the main movements
Why train anti-movements?
Why not just train movements? Well, you can certainly train all the movements you want, but it should be thoughtful and should have a why. Hopefully, you have the opportunity in your life to play games, participate in sports, dance, and explore as you desire. Obviously, in real life, you’re going to be rotating, flexing, extending, and bending. In terms of training, there are good reasons to focus on anti-movements.
Injury Prevention: Anti-movements teach dynamic/reactive stability. They teach your muscles how to stabilize and keep your spine safe.
Injury Prevention by Avoiding Repetition: If you believe McGill’s studies, repetitive spinal flexion and probably rotation can increase laxity/instability in your spine over time. A lot of chronic back pain is caused by gradually increasing joint laxity of the spine. Over time as we age, there’s more potential for your vertebrae to wiggle around and aggravate nerves, etc. Too much high-volume repetition can increase the probability of tweaking your back.
Practical Capabilities: Anti-movement/reactive stability exercise helps build real-life capabilities. Unilateral suitcase carries, anteriorly loaded squats & lunges, crawling, and hanging all teach your body how to exist in the real world. Dan John would say that they 'knit' everything together. I’ve found that regular suitcase carries, side planks, and hollow bodies just make everything else work better. If you can develop practical stability first, all sorts of other activities become more useful.
Sample Practical Core Training Session:
Spend some time establishing a neutral spine and moving your spine through a full range of movement warm-up. Cat camels, bird dogs, side plank pulses, empty hinges, hollow body, or dead bug variations, calendar girls, thoracic twists.
Consider doing a partner-assisted vertical plank as taught by Dan John. Partner B creates external forces while partner A resists: extension, flexion, left and right rotation, left and right lateral flexion.
Demonstrate and practice in a peer coaching setting the point of performance and relative cues for the following movements:
Some kind of anti-extension movement: I’d recommend either hollow body/bird dog work or suspension trainer fallouts. Crawls would fit the bill; they could fill in for almost any core work depending on needs.
Some kind of anti-flexion work: Romanian deadlift, good mornings, or superman holds could all be appropriate.
Some kind of anti-rotation work: Pallof presses are good but require bands. There are a lot of anti-rotation movements via one-armed plank hold. Elbow to palm plank walk-ups, one-armed plank, etc. If access to a rotation tool like a landmine or a long log, can do bus drivers or other anti-rotation work.
Some kind of anti-lateral flexion work: I prefer suitcase carries, but side plank variations have lots of advantages too.
As with all training, take time to identify the 'why' of your training. What are your goals for the session and your long-term goals? Don’t incorporate new movements just to entertain yourself. Consider how to progress and regress the movements depending on needs.
Finally, remember that core training is about more than just bending your spine forward. Try not to incorporate a high number of sit-ups or crunches unless you have a specific reason for doing so.
