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There may be no term more polarizing in our sports performance and fitness industries than functional training over the past decade. But in lieu of it’s popularity, it’s apparent that people simply don’t know the true meaning, theory or application of this type of training methodology.

Luckily, we have the “godfather” of functional training here with us dispelling the myths of functional training, and bringing forward the truth behind the many understood stigmas. Here is our interview with functional training expert, Dr. Craig Liebenson.

Rusin: There is a lot of confusion around the term “functional training” and how it fits into fitness, performance and rehabilitation. So lets set the record straight right off the bat. What is the real definition of functional training?

Liebenson: First off functional must be purposeful. So it “depends”. This is what athlete-centered programming is all about. It is not circus acts, “feats of strength”, or other nonsense. It must be training that is targeted to creating transfer to sport skill or residency.  

Functional training is related to your goal, plain and simple. If you play soccer there will be a large energy systems component. If you are female athlete in basketball, volleyball or soccer it would involve ACL injury prevention. A golfer or  baseball or hockey player – torsion power and control. What functional training is not is standing on one leg on a Bosu ball.

Rusin: That basic definition makes perfect sense. But why does functional training continue to be such a polarizing topic in athletic performance and fitness, and a confused on at that?

Liebenson: I suppose because the reaction to training isolated movements such as knee or elbow flexion or extension was to train whole body control on unstable surfaces. Of course we already had functional training. It was called general physical preparedness (GPP) which consisted of squats, deadlifts and bench presses. These complex movements were automatically functional and had great transfer to sports or other activities. At the end of the day functional is about transfer and skill acquisition. If an exercise enhances an individual’s skill, it would be considered functional.

Rusin: I get that nearly everything can be considered functional to the right person with specific goals, but what capacities do human beings need to magnify in their training to stay healthy and resilient against injuries?

Liebenson: Great question. Well first off we have a modern mismatch for prolonged sitting & sedentarism. These are causing a modern plague involving cancer, heart disease, obesity, diabetes & pain. So we all need more movement. Starting with getting upright & walking. Then, adding in deep squats (unweighted), walking on variable terrain without shoes, lifting occasionally, twisting, turning, stopping, starting, pushing/pulling, etc.. In other words as Guido van Ryssegem says “movement variability is the oil of the CNS”.  

Rusin: You’ve worked alongside some of the best coaches and practitioners in the world. Would you consider any of them functional training gurus? And is that designation actually a bad thing?

Liebenson: When I think of top experts in the field of functional training and fitness, I think of legendary coaches and practitioners like  Vern Gambetta, Mike Boyle and Dr. Stuart McGill. Vern was really the pioneer and I don’t begin to know his true place. However, when he says “know why you are doing what you are doing”, this is the key. We see this echoed in all the EXOS coaches when they remind us to be able to explain to your client/patient/athlete WHY you’ve chosen a certain exercise. As Dan John says, “the goal is the goal”. What is the person in front of us after? Weight loss, reduced cardiac risk, more energy, more tone? Or, less shoulder pain when they throw, knee pain when they run? Or, to stay healthier as they age?

For Mike Boyle he broke away from the Big 3 of GPP – squat, deadlift & bench press to focus more on the assistance moves. In particular, emphasizing 1 leg, split stance & injury prevention through anti-flexion, anti-rotation, etc.. Even in his work:rest ratios he is constantly reminding us to think about the outcome. What is the demand or expected capacity that the individual needs.

Like Jill Cook PT, PhD we have to bridge the gap between current and required capacity or else a tendinopathy will result. This is where my friend Professor McGill really shines. Assessing current capacity and asking the question what is their goal or demand. If they don’t have sufficient capacity for their demands then there is a “stability shortfall”. We not only need to bridge the gap but ensure there is a margin of error or stability surplus.

In an way all of this goes back to Professor Janda who highlighted that modern life involves an excess of sitting and sedentarism. A lack of minimum quantity and varieties of motion. So he emphasized that our “postural system” was becoming tighter and our “phasic system” weaker. This was termed functional pathology by he and his colleague Dr Karel Lewit. It was contrasted to the medical/orthopedic emphasis on structural pathology. Janda & Lewit for 50 years go us thinking about restoring a normal upright posture that would be resilient and anti-fragile during ADLs, occupational, recreational and sport activities. But, he never called this “functional training”.

I prefer to think that we evolved over 6 million years ago to be perfectly suited for nearly any challenge that can be thrown at us – except prolonged sedentarism. Since the agricultural revolution we have been in a decline which has accelerated in the last 2 generations because of the chair, desk, computer, cell phone, etc.

Rusin: You mentioned it already, but lets cut right to the chase on the topic of balance and unstable surface training. Would this be considered functional?

Liebenson: Let me tell you  a story. I worked for 4 years in the NBA with the LA Clippers. They used the Bosu quite frequently during 1 leg squats. Similar to how Juan Carlos Santana made it popular. One of their best players did this a lot. I noticed poor motor control at the ankle, but he was doing loaded exercises repetitively on the Bosu. I don’t know if there is a correlation, but he tore his achilles tendon. Very sad.

Do I use the Bosu? Yes, I will occasionally use it. But, we become slaves of our methods. If you have a purpose then go for it.

The problem with unstable surface training is highlighted by my example. If you don’t have control of your arches (transverse & longitudinal) and your knee (valgus) then adding sets, reps or load is only going to transfer compensatory patterns. I think most people know these limitations now. The ship of unstable training has sailed.

I’m more likely to reduce support from 2 leg to split stance to 1 leg to reduce stability. Rather than train on an unstable surface. Then, of course on one leg balance reaches are also a wonderful way to challenge stability. The ACL problem underscores how important balanced posture is. If our center of mass (trunk) is not over our base of support  (foot) that might be fine, but not if the knee is in valgus. The poor ACL is a tiny structure which fails at 2x bodyweight load non-traumatically in this situation.

Rusin: It seems as though many rehab pros have gravitated towards running a model of “rehab purgatory” and now this thought has started to creep into the sports performance and fitness world. Is there any merit to keeping an athlete or client on rehab based programming for the long term?

Liebenson: This is something which I’m guilty of. I’ve made this mistake & promoted this type of thinking. I hope I’ve learned my lesson. As Henk Kraaijenhof says when speaking of the minimal intervention required to achieve an effect ” do as little as necessary not as much as possible”. Gray Cook, PT has I think steered us towards the solution on this.

However, I feel the FMS coursework along with nearly all other “systems” with layer after layer of courses are actually part of the problem. Gray in explaining that the goal is 7 symmetric 2’s is telling us don’t worry about creating perfect 3’s. There are acceptable compensations. I think we get into trouble when we are pledging allegiance to the flag of DNS, PRI, FMS or whatever system instead of offering athlete-centered programming.  When a 2 is achieved it’s time to work on what Gray calls the “low lying fruit”. Find a 1 with unacceptable compensation and improve that.

This is where we need to know what the fundamental movement literacies are – the A,B,C’s of agility, balance & coordination. Then, build GPP on this base – squat, hinge, horizontal/vertical push, horizontal/vertical pull, carry, etc.

We must learn what our patient’s history is or athlete’s Key Performance Indicators (KPI’s).  Our program should alway be individualized and never be about our allegiance of a system. I love when Mike Robertson says he used to program for 4 week blocks but now even though it is much more work he programs only for 1 week blocks. Why? Because the rate at which people adapt or achieve skill acquisition varies! Everyone is different.

So back to your precise question. Policing perfection as Charlie Weingroff says is rarely good. To avoid rehab purgatory “let the methods serve the goals”. Get rid of pain (0’s); fundamental dysfunctions (1’s) & then begin to build capacity so it is above the requried level for that individual. In other words when there aren’t 0’s & 1’s it is time to “go hard or go home”. This is the mud that Greg Glassman refers to. But, unlike Cross Fit Greg – in theory – is talking about AFTER our fundamentals are solid.

Those keeping patients in Rehab Purgatory or turning their gyms into “corrective exercise” salons are forgetting that learning occurs at the edge of our capability.

Their must be some struggle. Creating this environment and reverse engineering drills to challenge our weakness is the role of the rehab specialist & trainer. Then, and most critically letting people explore movement challenges – so long as safety is assured – is the best way to learn. Being told what to do (i.e. bring your shoulder back and down, don’t poke your chin, tuck your pelvis,….) doesn’t transfer and always is not fun. We have Gabrielle Wulf to thank for this research which myself & Nick Winkelman have been trumpeting. Interestingly target cues, reactive training, etc is an ideal way to challenge people so they get into a flow state. But, rehab purgatory is the opposite of that.

Rusin: It seems as though a lot of performance coaches and rehab specialists devalue the power of progressive resistance training and loading in general. So that begs the question, is strength training inherently dangerous?

Liebenson: Holy Shit. That is scary. “your comfort zone is a cage, nothing grows there”. Once we have muted pain triggers and established baseline movement competencies it is time to grow some balls. Otherwise we will continue to go “boom & bust”. This is the take home message of Tim Gabbett‘s revolutionary research on load management. The problem is not so much overuse as under training. Of course we need recovery, proper sleep, better fuel, great mechanics, etc.. But, the biggest modifiable risk factor in sport is a high ratio of acute(1 week) to chronic (6 week) activity. In other words if we sit all week then play golf on the weekend our back will hurt.

If we go to training camp in High School, college or pro sports out of shape and then go through “boot camp” to get ready we will pull a hammie, injure our shoulder or hurt our back. Similarly, if rehabbing an injury if we rest and let pain be our guide then resume activity letting ” pain be our guide” this won’t work. And, finally to your point, if we do a lot of corrective exercises as rehab and then return to the sport without building GPP this will condemn us to more & endless cycles of rehab purgatory!

You are doing such a great job of highlighting the need for S&C principles to blend with rehab. David Joyce hammers at this as well and Gabbett’s work motivates us to watch our ramp. We need as Al Vermeil realized with the Bulls in the ’90’s & Dan Baker has emphasized for many years that we need to train hard year round. Lachlan Wilmot the S&C coach working with David Joyce in Aussie Football with the Giants is brilliant at programming the timing of high intensity lifts in-season. Also, how to modify based on injuries, colds, etc. As Joyce says rehab must be periodized and I believe this is the key to avoiding rehab purgatory.

Rusin: I of course agree, as strength is the foundation of our pain-free performance programming model. Going a step further, what role does developing strength and muscular hypertrophy play in the overall function of a human being?

Liebenson: Huge. Strength is the key to GPP and thus athletic performance. It is necessary to prevention of sarcopenia and frailty. If we look at squat strength it enhances speed in an athlete. Hypertrophy is an armor to an athlete.

Young athletes need to find their ideal combination of strength and speed as they develop. This requires training for hypertrophy with higher volume training until they have competed at the professional level for 2-4 years. After which volume may decrease but their PRs continue to rise. This will allow them greater recovery potential.

Rusin: Lets have a little fun, and actually bring these concepts around full circle for our coaches and clinicians reading to take action. What popular “functional training” exercises out there should people stop doing for general fitness?

Liebenson: Another great follow-up question John. Yes, trivial exercise without being likely to transfer is highly wasteful of time. This is a limited commodity. Dan Baker said it’s not what we’re capable of doing it’s what we’re able to do. Think of the NFL. The collective bargaining agreement (CBA) is a disaster for player health. Only the superstars can afford top off-season training programs. Now due to the CBA training camp is shorter. No wonder ACL injuries are taking off. This in a league with average career span of 3.5 years. What were they thinking?

So over-correcting or doing nonsense circus moves is a terrible waste of the valuable limited resource of training time. How many hours in a week can even an elite athlete possible train during their off-season? 10? 14? That’s it. Individualized programming that is constantly monitored for goal achievement is essential to maximize outcome. As Henk our greatest philosopher coach says “its not about output it’s about outcome”.

Yes, based on Gabbett’s work we are emphatically predisposing people to injury by over-correcting. But, please don’t mis-understand me. We don’t train in pain. We identify pain triggers and wind them down, teaching movement hygiene to reduce these pain markers. Then, we identify the painless dysfunctions that are the “silent killers” of athletic sustainability. Here we need the greatest experience and expertise to find the “tipping point” Dan Pfaff talks about of unacceptable compensations. This requires more than standardized examinations. As Profressor McGill says reliable testing is for the novice. It must be “real-time” assessment of the sport, practice  and training where “every exercise is a test”. Then, real-time intervention of what at ALTIS they call performance therapy.

A great rehab clinician or S&C athletic development coach knows that the key is athlete-centered management. We all work together instead of in silos. The athlete is in the middle not some technique system. Then, success becomes more natural because if the athlete’s “buy in” is key then we automatically need more “tie in” which only comes from having the mindset of skill transfer, resilience, performance, and athletic sustainability.

Rusin: For those people who aspire to lift forever, what are the non-negotiable aspects of programming that will enhance their durability and resilience against injury for the long term?

Liebenson: Hmmm. Boy you’ve got me thinking. #1 Find a great coach. Be patient. It’s not no pain no gain let your coach know what you feel.

Take the long view and focus on athletic sustainability.

Mastering your fundamentals and then building strength thorough lower volume, higher intensity training. Gradually building up your strength and being patient with plateaus and even flares. Each failure is a chance to learn.

In the end it will be by aggregation of marginal gains and the person who learns the fastest from mistakes will be the most successful.  

*For more information from Dr. Craig Liebenson, check out his:

Website: LA Sport & Spine

Facebook: Craig LiebensonLA Sport & Spine & Rehab 2 Performance

Instagram: @cliebenson

Twitter: @craigliebenson

About The Author

Dr. John Rusin

Dr. John Rusin is an internationally recognized coach, physical therapist, speaker, and writer, whose published over 300 articles in some of the most widely regarded media outlets in the industry like Men’s FitnessTestosterone NationMountain Dog Diet, and to name a few.

Dr. John works with some of the world’s most elite athletes, including Gold Medalist Olympians, NFL All-Pro Quarterbacks, MLB All-Stars, Professional Bodybuilders, World-Record Holding Powerlifters, National Level Olympic Lifters and All-World IronMan Triathletes.

Dr. Rusin is the leading pioneer in the fitness and sports performance industries in smart pain-free performance programming that achieves world class results while preventing injuries in the process. Dr. John’s 12-Week Functional Hypertrophy Training Program is the foundation of his methods, and is now available to you.


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