By Matt Cooper
Outside of making statements about nutrition, I’m not sure there’s a quicker way to get enemies in the training world than to talk about proprioception training—specifically, instability work. At best you bore people: minds drift to images of old-school physical therapy exercises on balance pads. At worst, you conjure up images of Neanderthals performing barbell back squats on BOSU balls, passing this along as “functional training.”
If you haven’t stopped reading or begun writing hate mail, please understand that there is a happy medium here. Just because you can do a lot of stupid things with proprioception training doesn’t mean that you can’t also use it properly. Done right, proprioception training can be a game-changer for raising the athletic ceiling. In fact, if you’re not incorporating the requisite dose and appropriate style of proprioceptive training, you can bet you’re leaving a lot of performance money on the table.If you’re not incorporating the requisite dose and appropriate style of proprioceptive training, you can bet you’re leaving a lot of performance money on the table, says @coopwiretap. Click To Tweet
Not only can you integrate proprioception into training systems, but it should honestly be a foundation of athlete remediation and a principle for continuously progressing the nervous system.
Theory to Practice: What Does the Research Say?
Before we dive in further, let’s take an inventory of just what has been established about proprioception training. I think it’s worth addressing both sides of the argument before the villagers mistakenly start knocking on my door with their pitchforks.
One of the main issues with instability training is that coaches, as people tend to do, make everything too black or white. The pendulum swings too far to one side or the other. Can’t we have properly dosed proprioceptive training while also accomplishing the other fundamentals? I believe so. I think the research can support this, too.
There are two fundamental problems most coaches have with proprioceptive training. The first is using it as a form of load progression—as a means to make exercises more difficult, rather than looking at resistance, load, speed, velocity, etc. The second issue seems to be conflicting research as to its benefit. Some coaches, like Bob Alejo, have quite eloquently advocated against proprioceptive training. For the record, I’m largely in agreement with that article and am fundamentally against instability training the way people execute it most of the time. I think a different understanding that yields a proper application is the remedy here.
Let’s talk load progression. As Bob Alejo cited, instability training as a means of making an exercise more difficult is not the answer and has mixed results, at best. This is the birthplace of the back squat on BOSU ball—a concept that needs to die off. But it doesn’t have to be one pipeline or another. What if we dosed enough instability, yet invested more of our time in more conventional exercise progressions?
Who’s to say that instability exercises can’t be a form of setting the table, neurophysiologically speaking, for the bread and butter performance movements of your training program? Might this be worth investigating?
As I’ll dig into later, I see trainers spending endless amounts of time on corrective exercises, movement prep, and other movement therapy work designed to ignite elements of neuromotor control/ability. Many of these overlap with proprioceptive abilities, as they stand. Why are people so averse to revisiting proprioception when they’ll just as easily throw an athlete down an endless, often system-less, chain of corrective chutes and ladders with no progression/exit/minimum effective dose strategy? That’s not to say that everyone doing these is doing them poorly, but it does happen with fewer side eyes than instability work.
The takeaway here is that these should not have been classified as exercise progressions, but rather as corrective exercise and movement prep.
As far as the research question goes, let’s take a look. As the aforementioned article and others have suggested, there is research against proprioceptive training. There is also research in favor of proprioception training. This data stratification in the form of a meta-analysis found that proprioception—and strength training—substantially tilted the deck for prevention and rehabilitation (flexibility stretching was the item found to have minimal effect). Proprioception training decreased injury by 45%, while strength training decreased injury risk by 69%. Here is another example demonstrating mechanical health.
Proprioception training can enhance performance, as well, such as developing speed and power. Proprioception can enhance explosive power via neural excitation, requisite input stimulus, and overall development of biomotor abilities during power and stretch shortening cycle activities (i.e., plyometrics). Even a poorly designed proprioception training program can drive these adaptations.
Confused yet? It’s okay. Yes, there is conflicting research with proprioception training, but then again, there is conflicting research with many other modalities, methods, and principles in the athletic performance world. Sensory training is hardly a four-leaf clover here.
Let’s also look at the issues with these studies. There are actually a number of factors at play here that I feel may unfairly stack the deck against properly executed sensory training. First, we have to consider the population—whether we’re measuring trained individuals or not. Physical therapist Fabrice Gautier states that, “Many studies have been made on strength-type or fitness athletes—obviously, you’re not going to ask a powerlifter to do a eurostep in traffic at full speed. Most athletes across basketball, soccer, football, hockey, rugby, etc. will agree that while the game is played on a stable surface, once the game starts it’s no longer a stable environment.”
Second, there’s poor program design. Many of these studies pit instability training exclusively against another exclusive type of training (e.g., strength training, agility). Is this really how anyone reading this would actually train an athlete? This doesn’t answer whether proprioception training is good—it just answers whether it’s better than some other modality as an isolated variable. That’s hardly useful for drawing meaningful conclusions.
Next up, we have poor exercise modality selection and inferior equipment. In both supportive and detractive studies, many of the exercises are what you would call dumb—scientifically speaking, of course. When we test whether something is valid, shouldn’t we test the best of the best?I believe the research, fractured as it may be, does still support proprioceptive sensory training as a singular component within the framework of a larger training system. Click To Tweet
Regarding the training equipment, I’m actually not a fan of most proprioceptive devices. But we shouldn’t extrapolate this to mean that all sensory training is poor. If you drove a car from 20 years ago, you wouldn’t assume that all cars are lacking or that driving a car in general is bad. Build a better mousetrap. A BOSU ball is hardly the same thing as a Waff or similar device.
I believe the research, fractured as it may be, does still support proprioceptive sensory training as a singular component within the framework of a larger training system.
Building a Better Nervous System
Any athlete who wants to be on the path to true fitness must accept that nervous system training is essential.
“There are basically three aspects of nervous system function that can be improved [in an athletic sense]: processing more information, processing more information faster, or processing more information faster to and from the brain. In some cases, the information can circumvent going to the brain altogether and move to and from the spinal cord, making the processing of information even faster yet.”–Marv Marinovich & Dr. Edythe M. Heus
In order to improve in these ways, the nervous system must, in part, gather information about the position, movement, posture, tension, autonomic readout, and changes in equilibrium of the body. Your internal awareness of your body’s place in this context IS proprioception. Kinesthetic awareness is technically proprioception in space. (Please note that some people, including me, occasionally use these terms interchangeably.) These sensory nerves are located throughout the body, including in the middle ears, ocular nerves, muscles, ligaments, tendons, skin, and joints. These proprioceptor sites are responsible for collecting this key athletic information.
Once the brain has data collected, it sends out control orders in the form of signals to muscles. As sporting movement continues, these sensory nerves located throughout the body continue to transmit new information about the body’s changing position to the brain, which sends out new orders to fine-tune the movement. The more refined these proprioceptors are—potentially through training development—the better the information network and the better the movement.
I believe it was Heus who first likened proprioception to walking in the woods at night. Imagine you have little flashlights all over your body. The more developed your proprioceptors are, the brighter the light. The brighter the light, the better you’re able to see what’s around you. The better you can see, the better you can respond to your environment and move through the world.
“Success in a particular event depends on the motor programming that initiates a proper biofeedback signal to the motor pool.” –Gideon Ariel
Trainers tend to think outward in terms of chosen exercise modalities. In other words, they have a black box understanding of concepts. Protocol X nets us Y result. Input X=Y, but what about when it doesn’t? What’s going on in the middle of that equation? Maybe if we can mine that physiological understanding some, we can extract some gold. I think it was the Eastern Bloc sports scientists and later Dr. Ariel who first compared athletic performance to a computing system—a complex interaction of physiology in the body known as biocybernetics.
I bring this up because most people tend to flip past the real learning in favor of the sets and reps tables. Hell, we’re all guilty. But the truth is that the things we are trying to affect with this programming—motor unit recruitment, innervation, rate coding, motor engram coding, myelination, etc.—are all prefaced by foundational proprioception. This is why I believe program design models should give a distinct preference to the development of physiological qualities (some quantitative, some qualitative) in various phases.
Physiological Program Design: Honing the Athlete’s Reactive Ability
From here, the human machine can do its thing and respond better to additional training and instructions. The intricate arrangement of muscles, bones, connective tissues, and neural control accounts for all muscular activities. Performance starts in the nervous system (or stimuli that cause activity in the nervous system) and propagates outward from there, according to physical cause and effect laws. As we’ve covered, this is first determined by central and peripheral sensory programs.
Now for the fun part—going from theory to practice. This is where we can convert physiology into actual work in the trenches.
You’ll recall from earlier that the more accurate the information the brain has, the more accurately it can tell the musculoskeletal system to accomplish a task efficiently. This allows you to improve your reaction time. A singular reaction is made up of sensing time and decision time: the time demands to sense the need to move and the time demands of actually making that move. The better the proprioception, the quicker the sensing time. The more accurate the nerve circuit pathways used here, the quicker the decision time. The absolute hairline-trigger decision times use the reflex arc.
This is also known as the propriospinal process. This means that instead of information taking a longer route from the sensory nerves of the peripheral nervous system (PNS) to the spinal cord, then the brain, then back again, it will circumvent going to the brain and go from the PNS nerves to the spinal cord and back again. Taking this neural detour and eliminating the travel time to the brain trims down decision and reactive ability time demands, making movements even faster. In other words, the nervous system has been highly developed to react as quickly as if it were a reflex. You have no doubt witnessed this hairline-trigger nervous system response in professional sports.
Video 1. Here, I use proprioceptive pads in the early stages of program design—the athlete remediation phase, as it’s taught by Nick Curson. This is not dissimilar to what Steffan Jones and Frans Bosch would call skill stability work.
Following assessment, we are essentially developing biomotor abilities. There are plenty of ways to attack this, and in some ways the only limits are your own creativity. Here, the goal is to layer an athlete’s sport-specific motor skills over proprioceptive biomotor development. The resultant effect is the heightened development of aforementioned neuromuscular integrations due to central nervous system (CNS) and PNS awakening. Obviously, this isn’t where the train stops, but this alone often causes athletes’ sporting movement, positioning, and posture to improve. You have to play around with various angles and progress the athlete through different positions here.
According to Gideon Ariel, in 1935, one of the founding fathers of modern biomechanics, N.A. Bernstein, first compared the inner workings of the athlete and their movements to a symphony orchestra:
“Each instrument plays its individual score. So in the act of walking, each joint reproduces its own curve of movements and each center of gravity its sequence of accelerations; each muscle produces its melody of efforts, full with regularly changing but stable details, and in a like manner the whole of this ensemble acts in unison with a single and complete rhythm, fusing the whole enormous complexity into a clear and harmonic simplicity. The consolidator and manager of the complex entity—conductor and at the same time composer of the analyzed score—is, of course, the central nervous system.”
By extension, I have found it useful to include proprioceptive training as a wake-up drill for practice and game play. Conceptually, by purposely throwing the body off-balance via instability, we destabilize the athlete. The aforementioned sensory nerves monitor what needs to occur in the muscles and then sends rapid-fire messages to the spinal cord and brain. In context, the message is, “Help, I’m going to fall!” The body then directs the musculoskeletal system via motor nerves to carry messages back to the muscles to make minor muscular adjustments. The more challenging it is for the systems of this nerve grid to find balance, the more efficient they become at finding it, training the body to react and self-correct faster.
Remember, the brain works on a protect-to-perform continuum and is hardwired for survival. The added element of danger helps switch on more neural “triggers,” priming the athlete for future movement. This is based on the nervous system’s propensity to stagnate in training. If left unchallenged or understimulated in one area, the brain will always use the least amount of resources possible to get from point A to point B. Overstimulation or development in one type of training or movement pattern (e.g., maximal strength, sagittal overemphasis), as well as understimulation via one set of environmental stimuli conditions (flat plane, surface, speed), are examples of how the nervous system can stagnate in training.
Bulletproofing the body from injury, as well as proper rehabilitation and reconditioning, requires this foundational development of the nervous system and its dialogue with the musculoskeletal system. Without putting a blanket term over every single practitioner, traditional PT models obviously integrate the nervous system, but often either slow its development or feature poor proprioceptive exercise modality selection. This is one of the reasons there is a gap between rehabilitation and return to play.
We’ve identified how tuned proprioceptors create a foundation of integrated human movement. If you look at many modern corrective exercise and movement prep methods, these are all various ways of taking output-based training (non-direct lines of communication with the nervous system) and using them to manipulate the input (nervous system). Functional range conditioning, Postural Restoration Institute, functional patterns, dynamic neuromuscular stabilization, neurokinetic therapy, and others all advocate for athlete integration and proper groups of prime mover and intrinsic muscles firing in sync, as described earlier.
Innovators such as Da Vinci, Ariel, Marinovich, Bondarchuk, and others have all had their own unique way of describing this concept. If you truly read Transfer of Training cover to cover, you’ll see Bondarchuk put it quite eloquently in that it is necessary to mimic specific muscular firing sequences in training.
Many quality practitioners today are taking this information and ensuring that athletes train in an integrated manner. Nick Curson’s work at Speed of Sport is an excellent example of this. Dr. Pat Davidson is also great at translating this into quality biomechanical training models for the human athlete.
A major piece here is not just engineering higher performance, but also the concept that if the athlete trains their muscles, planes of motion, and positions in more of an integrated manner, they will present with fewer postural, structural, movement, performance, and overall mechanical pathologies. This has significant downstream implications on injury resilience.
“Most sporting injuries are a proprioceptive issue—muscles fire at the wrong moment of a movement or change of direction when they should be protecting the joint,” says Nick Curson. “If the majority of your training is purely in a linear and controlled manner in the gym over and over, yet the sport is not controlled nor linear, you are asking for trouble.”
ACL tears are seemingly becoming more common in pro arenas like the NBA, as well as in youth sports. In fact, the number of ACL tears in student-athletes ages 6-18 has been on the rise to the tune of about 2% per year for the last 20 years.
There’s plenty to speculate about. Evolving sporting demands? Cushy shoes? Fear of properly loading the athletes? Overemphasis on traditional, flat-footed lifts? Poorer food quality leading to chronic inflammation? Who knows? It’s difficult to triangulate with precision, but there seem to be some clear advances in research and technology. Yet they aren’t necessarily leading to better exercise modalities and training systems.
As part of a larger training system, proprioception training can help mitigate injury, promote proper muscle activation patterning, and lap traditional rehab time, says @coopwiretap. Click To Tweet
In the image above, I’m working with an athlete on reintegration from a major injury using a top-down, inside-out approach. The use of novel proprioception training is just an ingredient in the recipe, but as part of a larger training system, it can help mitigate injury, promote proper muscle activation patterning, ensure less time is needed for corrective exercise, and lap traditional rehabilitation time.
Neuromuscular Assessments and Profiling
In addition to it being a rehab and performance method, presenting athletes with instability can also serve as an assessment tool. Muscular co-contraction, relaxation, muscle chain recruitment preferences, balance, breathing, and asymmetries are some of the things to look for during assessment. Fabrice Gautier, the main private NBA physical therapist, has developed sophisticated athlete neuromuscular profiling assessments.
“I have been using the Waff in athletes for nine years now—primarily as an assessment tool. Proprioceptive pads allow me to see many motricity preferences of the person—it ignites sudden archaic reflexes that reveal many underlying postural and/or neural deficiencies. We then can go into a properly progressed corrective and loading program from here. I think proprioception training is mistakenly thought of as pure balance work, when in reality it’s about the ability of the CNS/PNS to integrate challenges in reaction, performance, and postural awareness.” –Fabrice Gautier, PT
Nervous System Progression and Potentiation
Properly executed proprioception training can seriously raise the ceiling of performance in athletes. The neural excitation and potentiation produced during both static and dynamic positions of instability can help athletes develop or reclaim lost athleticism.
“You’re never purely doing rehab or performance training. You’re doing both.” –Garrett Salpeter
Coaches often conform to wholly traditional exercises alone at the expense of neural dynamism. This can do more harm than good. So, the question is, what does a quality loaded or performance proprioceptive exercise look like? I’ll offer dynamic and static examples.
Post activation potentiation using proprioceptive isometric holds followed by plyometrics is a phenomenal combination for athletic development, says @coopwiretap. Click To Tweet
I’m a fan of positional and isometric holds with requisite breathing patterns. The use of isometric hold variations for neural excitation, muscle activation, strength, power, and athletic ability has been well-documented. By injecting the instability component in certain cases, we can potentially provide a more global and complete nervous system stimulus.
I’m also a fan of various positional instability holds as an on-ramp from the prehab portion of training sessions into the working sets. Post activation potentiation using proprioceptive isometric holds followed by plyometrics is a phenomenal combination for athletic development with measurable quantitative and qualitative improvements (e.g., muscle EMG, vertical jump, speed metrics, velocity, etc.).
Video 2. Isokinetic load—an example of a proper way to load instability.
A loaded proprioceptive exercise? Blasphemy! Before the villagers come to my door with pitchforks, please note that this is a hydraulic, adaptive isokinetic resistance, not a barbell back squat. The goal here is to not only provide the neural stimulus, but also develop the micro muscles in the lower leg and other smaller, stabilizing muscles that contribute to sporting movement. This also helps develop the tiny intrinsic muscles located along the spine that are responsible for controlling the other limbs in space and overall athletic ability.
The athlete is also able to perform this with some degree of speed in a safe environment. The load does not involve bracing a weight. In fact, it’s more about the force the athlete can apply against the machine as seen in iso-inertial training (e.g., proper sled work). This has a different neural adaptation and gets the brain out of its protectorate mode seen in the default mode network.
After stimulating this biomotor ability floor, we can go a number of ways. In really young athletes with minimal development, this provides a great training stimulus in heavier doses. In my own practice, I’m careful to identify when to load a certain position versus when said load (or threshold of load) may result in a decreased neural adaptation. One direction to go with this is to first load the athlete in this manner and then go into a loaded exercise (e.g., rear foot elevated split squat or hand-supported safety bar split squat). The idea is that you go into that subsequent loaded exercise with a full deck of cards, neuromuscularly speaking.Regular dosing of proprioceptive biomotor development in key training movements enables the athlete to capture the benefits of both the loaded exercise and the unloaded proprioceptive one. Click To Tweet
Another protocol I use is regular dosing of proprioceptive biomotor development in key training movements. This enables the athlete to capture both the benefits of the loaded exercise and the benefits of the unloaded proprioceptive one. I find this ensures that the athlete does not overdevelop the prime mover muscles from heavy loads at the expense of the smaller, synergist muscle groups.
Video 5. Here is a quick example of a perturbation core exercise in MMA athletes. Yes, one athlete falls off at the end, but that’s part of the game in this case. I don’t mind seeing this in a few of the dynamic exercises I’ve used over the years. The element of “play” in this drill and stimulated danger in the sensory nerves heightens the neural excitation.
My advice here? Use your creativity, but also your common sense.
The Good, the Bad, and the Ugly: When Not to Add Instability
If you’re still with me, I appreciate you taking the time to read this all the way through with an open mind. Of course, no proprioception article could be complete without a “do not try this at home” section, right? With that said, let’s go through a quick commonsense primer on what proprioception training is not and when not to use it.
First of all, do not be the guy who barbell back squats on a BOSU ball. There’s intelligently using proprioception training and then there’s dangerous idiocy. Substantially loaded movements on instability are just asking for trouble.
Start simple. There are many ways to drive proprioception/sensory training and the simplest may be training barefoot. This is the place to start with athletes. According to strength and conditioning coach Paul Fabritz, “This alone can cause significant change throughout the body because our feet are the foundation. Even minor dysfunction can cause catastrophic problems in the knees, hips, and back.”There are many ways to drive proprioception/sensory training and the simplest may be training barefoot. This is the place to start with athletes, says @coopwiretap. Click To Tweet
Don’t be the guy who thinks EVERYTHING can be improved by adding instability. You still need ideal turf conditions to generate the maximal amount of force. Hard, flat surfaces generate the right type of kinesthetic feedback for you to maximally express that nervous system. So yes, continue to do things like sprinting, Olympic lifting, etc. as you were. Don’t think that doing a hex bar deadlift off of a cushy box is the answer.
At the same time, don’t be the guy who neglects a powerful tool just because it’s often in the hands of morons. Proprioception training (and “functional training” on the whole) has gotten a bad rap because of its practitioners. This doesn’t mean that everything this arena has to offer is impossible. Fireworks can be awesome, or a few idiots can ruin them for everyone.
Think critically about the research. As you’ve seen, there’s a litany of unstable surfaces, tools, and exercise combinations to use. Thus, it’s pretty hard to parse through research and assume that the different conditions and variables being tested are going to directly transfer or not transfer at all to your own programming results. Use research to guide your training, but don’t be afraid to do some safe, intelligent, informed n=1 citizen science.
Above all, be safe. Don’t neglect common sense to develop your sensory nerves.
Please note that this was a mere toe dip into the world of refinement of the athlete’s kinesthetic sensory system. Many more exercise modalities and iterations of sensory training exist. This was meant to convince you to reexamine this type of training, not serve as its Bible.