An Example of How I Use the Biopsychosocial Model to Explain Pain

Recently I received the following comment on an old blog post of mine:

“I had an injury to my hamstring and sprained my SI ligaments. I had PRP done but over time due to compensation developed a rotated pelvis and a left on right sacral torsion. My L4 facet got stuck in extension for over a year. I left my PT and found a different one that unlocked it in less than a minute. Being stuck like that did serious damage to my body's ability to stay straight. My facet continues to get stuck. I also went to see another specialist and found my tailbone was completely out of place offsetting my center of gravity. I follow the PRI upper body pattern with a tonic right neck from being right handed and sitting at a computer all day, which does contribute to my gait issues however my lower body is somewhat different than the PRI model and my physical therapist tells me the same thing. My right hip is forward compared to when I stand on my left foot most of the time which is opposite the PRI philosophy. I make my back pain worse when I do the PRI exercises for the lower body. My enter body is a mess, twisting all the way up the spine. My L4/L5 is twisted causing issues at T4 and at my neck. Have you found anything to help you fix [a] rotated pelvis?”

I really appreciate it when people take the time to read some of my posts and to also share their personal experiences with pain, which isn’t always an easy thing to do because pain freaking sucks. I always try my best to respond and to answer as many questions as I can to add more of my perspective to the discussion in the hopes that people find it helpful. There were a lot of topics to unpack in what this individual shared, and I actually encounter many patients in my practice who share very similar testimonies and what I believe are erroneous thought processes behind why we experience pain. I wanted to share my response to the above in this blog post in the hopes that it may elucidate more viable mechanisms behind why we experience pain, which will hopefully help more people recover from and manage their chronic pain.

My response:

Thanks for sharing your experience about your pain. I hope you're experiencing improvement or receiving care that is helping with the issues you mentioned so you can go back to doing the things you love with as little pain as possible.

In regards to some of the issues you mentioned, such as the L4 facet being stuck in extension for over a year, your tailbone being out of place and your twisted L4/L5 disc causing thoracic spine and neck pain: These are very hard, "pathoanatomic" explanations for why someone is experiencing pain, and are characteristic of something called the "subluxation model" of pain which is being increasingly challenged as it fails to take into account many other important reasons why someone has pain (with pain neuroscience and psychosocial factors also being large components of someone's pain experience).

To explain in other words, our bodies don't experience pain because they get mechanically "stuck" in certain positions, and when we recover from injuries and pain it's not because those joints or body parts become physically un-stuck or moved back into place. There is very poor reliability when it comes to assessing things like the relative position of a sacrum or ilium (the bones that comprise the sacroiliac joint), and such a weak relationship serves as an insufficient model to explain why someone might be feeling pain there. This concept can be extrapolated to lumbar spine facet joints, tailbone positions and trunk rotation asymmetries. While anatomically, it's possible for there to be small, reduced motion in certain joints in the lumbar spine or surrounding our hips/pelvis, these joint mechanics don't necessarily need to be completely resolved nor restored to symmetry in order for someone to be free from pain.

There is no default, neutral, postural orientation of symmetry that our bodies need to be in in order to feel "normal", and pursuing this as a rehabilitative goal poses the risk of trapping an individual into thought patterns and false pain narratives that may ultimately be irrelevant to one's recovery, or even worse, make the pain increase. A nocebo is when there is a negative health response due to negative expectations or false beliefs about pain. Example: "I'm noticing that my pelvis is tipped forward more on the right than on the left, making this leg 0.75 cm longer than the other, which is jamming my facet joint on the right side which is spreading pain up into my mid-back and neck." This thought pattern in which a small, probably inconsequential biomechanic like a leg length discrepancy triggers a cascade of physical impairments that is unreliable and very poorly related to pain can lead the individual to actually literally feel more pain in all those regions.

There is no default, neutral, postural orientation of symmetry that our bodies need to be in in order to feel “normal”, and pursuing this as a rehabilitative goal poses the risk of trapping an individual into thought patterns and false pain narratives that may ultimately be irrelevant to one’s recovery, or even worse, make the pain increase.

SOME (again some, not all) physical therapists who use a PRI approach utilize this kind of thinking when applying their PRI-approaches and treatments to individuals experiencing chronic pain, and it's that kind of approach that I think requires more scrutiny and critical thinking. In the time that has passed since I wrote this blog post, my criticism has more to do with the explanation/thought-process/narratives that health care professionals employ, and not necessarily against PRI itself. There are individuals out there who use PRI-influenced concepts responsibly, taking into account that there are other biological, neurological and psychosocial mechanisms at play which all influence pain.

Rather than trying to un-twist a vertebral disc back into neutrality, or to get a pelvis on one side to face forward by one or two inches more, an approach that takes factors other than strict biomechanical rules into account (such as pain neuroscience and how the central nervous system processes pain) is to build up your body’s tolerance through load management, strengthening and graded exposure to motions and positions that are currently uncomfortable.

Rather than trying to un-twist a vertebral disc back into neutrality, or to get a pelvis on one side to face forward by one or two inches more, an approach that takes factors other than strict biomechanical rules into account (such as pain neuroscience and how the central nervous system processes pain) is to build up your body's tolerance through load management, strengthening and graded exposure to motions and positions that are currently uncomfortable. This may seem like the same thing but the distinction is very important. Our bodies are resilient and adaptive, and don't need to be in a particular orientation of symmetry to recover from pain. I'd be happy to discuss this more with you if you'd like as this is a lot of information to unpack and I don't want to just be another person who gives you conflicting information from what you've received and just complicates things further. Happy to send you some more information resources as well if you'd like, if so just email me at Thanks again for following this post/comment thread and I wish you the best!

Course Review: Tim Gabbett’s Training Smarter & Harder Workshop, Acute/Chronic Workload Ratios and Implications for Powerlifting

Earlier this year I had the pleasure of attending a course called Train Smarter and Harder, taught by Dr. Tim Gabbett. Dr. Gabbett holds a PhD in Human Physiology and another in Applied Science of Professional Football (that’s non-American football). With over 20 years of experience, he has worked with elite collegiate and professional athletes worldwide including Olympians and Commonweatlh Games competitors. A prolific researcher, he’s published over 200 peer reviewed articles on various topics including acute/chronic workload ratios (more on that later), athlete monitoring, rugby, Australian football, basketball, volleyball, handball and more. As a highly-sought speaker who has presented at over 200 conferences around the world, I jumped at this opportunity to attend his seminar here in NYC especially since he makes his home all the way in Australia. The following will be a brief course review of some of his main talking points as well as some of my thoughts on how this can be applied to reducing the risk of injury in the sport of powerlifting.

Injury Risk Reduction

Currently, we unfortunately don’t know much about “preventing” injuries per se when it comes to competition and training for sports, but as clinicians who work in sports rehabilitation we can try our best to reduce the risk of injury by combining what we know about musculoskeletal health with the available body of research on the topic. I wanted to attend Gabbett’s course as I understood some of his research sought to quantify specific workloads that athletes could perform which could inform varying degrees of relative injury risk. Could there actually be an objective way to determine how much training is too much training? Can you analyze an athlete’s current training program and with some measure of reliability estimate whether he is putting himself at risk for injury or protecting against it? What metrics do you even look at?!

Figure A: Modified Workload Injury Aetiology Model

Figure A: Modified Workload Injury Aetiology Model

In researching some potential answers to these questions, Gabbett made some modifications to an athletic injury etiology model (see Figure A) originally designed by Meeuwisse et al, 2007 depicting the multifactorial, non-linear nature of athletes’ injury risk. Suppose you’re an athlete with a certain level of injury risk, based on history of injury, factors you can control (aerobic capacity, strength, motor control) and factors you can’t control (age, bony anatomy, genetics). Your training program for your sport consists of resistance training, cardiovascular training, sport-specific skill practice and more. All these things are examples of stimuli which impart load, or work performed in preparation for your sport. Workload is the “cumulative amount of stress placed on an individual from multiple training sessions and games over a period of time.” (Gabbett et al, 2014).

Workload is the “cumulative amount of stress placed on an individual from multiple training sessions and games over a period of time.”
— Gabbett et al, 2014

Ideally, you perform your training well which yields positive, physiological adaptations that contribute to your fitness. Naturally, experiencing fatigue is a part of this process. The net balance between managing your fitness and fatigue influences your internal injury risk factors in either a positive or negative way, and of course you want fitness to exceed fatigue in order to yield healthy performance.

Performance = Fitness - Fatigue

When we do occasionally experience injury and undergo recovery/rehabilitation, we continue to impart workload and remain in the cycle to (hopefully) drive more positive physical adaptations that result in healthier, improved sport performance. As you can see from Figure A, load is the vehicle that drives athletes to or from injury. As Gregory Lehman has similarly stated, load is both the poison and the antidote. When a tissue’s capacity to tolerate load is exceeded, it results in injury. But a healthy, tolerable loading dosage actually promotes resilience and decreases the chance of fatigue leading to injury. A key principle here is that even when you’re injured, your body needs to undergo some degree of loading to eventually recover and be healthy again.

Context & environment affect the load/load capacity relationship. From Verhagen, 2018

Context & environment affect the load/load capacity relationship. From Verhagen, 2018

Another related model on the relationship between load capacity and performance by Verhagen, 2018 mentions how temporal factors such as context and environment can heavily influence the balance between the two. Things like fatigue, stress, mental state, emotion and motivation can drastically change how your body responds to a given load from day to day.

Enter Acute/Chronic Workload Ratios

Gabbett’s research on the Acute:Chronic Workload Ratio (ACWR) has been a popular podcast topic over the past couple of years as it has been proposed as a model to objectively measure an athlete’s readiness (or lack thereof) to train. In its most simple terms, it can be measured by dividing the amount of workload of the current week by the average workload of a longer period of time (usually 4 weeks). One method of calculating workload is to multiply an athlete’s reported RPE (Rating of Perceived Exertion) by another metric of a bout of training, such as duration.

For example, on Monday an athlete performs a 30 minute bout of training with an RPE of 5; on Wednesday, a 45 minute bout at RPE 6 and on Friday, a 60 minute bout at RPE 7.


Let’s say this this is a typical week of training, so the sum of the week’s workload is 840 arbitrary units (AU). Let’s also say the athlete does this for four weeks, which puts the chronic workload at 840 AU.

Now, let’s say in the fifth week this athlete participates in a competitive three-day tournament in which he competes for 60 minutes at RPE 8 each day. His acute workload for this week is 1,440 AU (480 AU x 3).

The ACWR in this scenario would be 1,440/975, or 1.71.


Gabbett’s research suggests that certain athletes whose ACWRs exceeded 1.5 experienced injuries at rates as high as 2-4x greater than athletes whose ACWRs were < 1.0. Additional research which observed ACWRs and injury rates among cricket, rugby and Australian football players suggests that 0.8 to 1.3 is an ideal ratio range to minimize injury risk. The graph above shows these zones on a graph that depicts these ratios as a training “sweet spot” to aim for and a training “danger zone” where risk is elevated.

ACWR and Powerlifting

As a powerlifter & physical therapist I’m pretty fascinated with the concept of estimating and quantifying injury risk in the way Gabbett has done, and the degree to which these calculations can be applied to barbell sports. Gabbett’s work and research was performed exclusively in field sports such as football, rugby and cricket where measuring internal load through the athletes’ self-reported RPE was probably the most practical and easy way to estimate load. But how about a sport in which there are very objective measures of external training load, such as sets, repetitions, weight, bar distance traveled, time under tension and bar velocity? RPE exists as an effective proxy for training intensity in the context of programming and load selection purposes, especially given the potential day-to-day or week-to-week changes in a lifter’s readiness. But after your training sessions if you have all this objective data from your lifting performance (literally the weight you lifted that was on the bar) I think it could also be helpful to infer injury risk models from that.

A lot of the principles that were taught in Gabbett’s seminar described the foundational tenets of progressive overload in powerlifting programming and strengthening and conditioning for the long term in general. Impose physiologic adaptations upon the body through gradually increasing amounts of work over time, paying attention to spikes in workload that the athlete may not necessarily be prepared for. The more data you accumulate over time, the better idea your coach has about how your body responds to different parameters of training and the more effectively able you’ll be able to elicit desired adaptations from different zones of training, which each have different indications.

There was much emphasis in the course of building a strong foundation early on in the athlete’s “season”, or establishing a robust chronic workload base to better enable you to take on greater microcycles of intensity or volume later on, especially as you near the end of a training block or approach a testing day for a heat check. If you zoom out even further on an athlete’s training life, having a long training age (say, a decade or more of experience in effective strength training) your body may be even more prepared to take on voluminous macrocycles with less health issues than your less-experienced counterparts.

Measuring ACWRs are basically ways to quantify the maximal recoverable volume (MRV) for an individual lifter. While I don’t think that there exists a specific ratio for all lifters to keep underneath (as some evidence suggests that 1.5 is that special number for for rugby, cricket, Australian football players and perhaps similar field sport athletes), the ACWR can be another numerical tool to inform coaches about their athletes’ current readiness based on recent historical performance in the short term and medium term. There will be different ratios between different lifters, and also potentially different ratios within a single lifter depending on type of lift (squat vs. bench vs. deadlift) and training intensity zone. For example, I think it would be more accurate to measure an ACWR for the deadlift which is separate from the bench press. And take the squat for example, a novice or intermediate lifter may have a lower ACWR ceiling for intensities at 90% 1RM and greater, but has a much higher MRV between 65% and 85% 1RM. There are myriad ways to make these calculations and observations.

Calculating Your ACWR

I’ve created this sample spreadsheet to help coaches and lifters calculate and monitor ACWRs. Once you access it, go to File and Make a Copy of spreadsheet so you can edit the document and enter in your own values. Feel free to make a copy for every lift you’d like to measure your ACWR (i.e. separate sheets for squat, bench press and deadlift).

The values you see in the sample I’m providing below are my squat volumes for one of my final blocks leading into last year’s Raw Nationals in Spokane, where the majority of my squat intensities were at 90% or greater. My squatting frequency was 2x/week during this block.

I’ve entered in my daily volumes for each of the four weeks of the block, and the Weekly Volume cells automatically populate:


The next two sections calculate your Average Weekly and Average Daily Volumes, and from that you can see your ACWR by week and also by day. You can use these charts to see trends in your week to week and day to day progressions. Notice that my volume started off high and gradually decreased. While my intensity data is not shown, it increased gradually through the block. My ACWR also decreased as I progressed through the block which suggests that my risk for injury decreased even as I was peaking.


In my final week leading into Spokane I hit my squat opener and some lighter back-off sets. I entered my volume for one squat day and also on the week into the blue cells to calculate my ACWRs for this last week, which were very low (as they should be leading into competition).

(Shout out to my Coach Sean Collins of Murder of Crows Barbell Club in Brooklyn, NY who does all my programming and safely quarterbacked me through this peak, which resulted in me PR’ing on my bench press, deadlift and total at Nationals.)

Final Thoughts and Implications for Physical Therapy

I found Dr. Gabbett’s course to be very informative and helpful. The course attendees consisted of physical therapists, strength coaches and personal trainers, many of whom also coached various sports such as gymnastics, track and field, basketball and more. Throughout the course, we broke up into small groups and discussed programming scenarios for different sports while calculating ACWRs for each one. While I think the course would be most helpful for PTs who work primarily in sports rehab settings or who see mainly athletes, there’s definitely a lot of content that physical therapists could apply to general populations as well.

I found a lot of similarity between this course and the Functional Anatomy Seminars (which I also wrote a review on a couple of years back, for FRC):

  • Injury = Load > Capacity    Performance = Fitness - Fatigue

  • Earn the right to push yourself hard in training by first preparing your body to tolerate the loads you’re going to place on it. Establish that foundational base first and maintain a robust chronic workload. If you go ham all the time in training without locking down the training prerequisites first, you’re putting yourself at risk for injury.

  • “Getting hurt in training isn’t always an overuse injury--it’s an under-preparation issue.”

  • “It’s not the load the breaks you down--it’s the load you’re not prepared for.”

There’s a lot of therapeutic benefit in applying these concepts on individual joints, specific body regions and frequently used movement patterns that experience recurrent injuries or dysfunction. Recognizing and diagnosing these as well as focusing rehabilitation specifically on those joints/regions/patterns through smart loading management is a crucial aspect of sports rehabilitation.

Dr. Gabbett is a great speaker and even with dozens of people approaching him during breaks and after the course with very sport-specific, esoteric questions, he was always patient and willing to engage in conversation with you. Would highly recommend this course.

Tim and Me

Tim and Me

The group!

The group!


1) Bourdon, P.C., Cardinale, M., Murray, A., Gastin, P., Kellmann, M., Varley, M.C., Gabbett, T.J., Coutts, A.J., Burgess, D.J., Gregson, W., Cable, N.T. (2017). Monitoring athlete training loads: Consensus statement. International Journal of Sports Physiology and Performance, 12:S2161-S2170.

Gabbett, T.J., and Whiteley, R. (2017). Two training-load paradoxes: can we work harder and smarter, can physical preparation and medical be team-mates? International Journal of Sports Physiology and Performance, 12:S250-S254.

3) Malone, S., Owen, A., Newton, M., Mendes, B., Collins, K., and 
Gabbett, T.J. (2017). The acute:chronic workload ratio in relation to injury risk in professional soccer. Journal of Science and Medicine in Sport, 20:561-565.

4) Quarrie, K., Lambert, M., Mellalieu, S., 
Gabbett, T.J., Gray, A., Hennessy, L., Stadelmann, J., Fuller, C., Gill, N., Blackie, J., Kemp, S., Cook, C., Nicol, R., and Raftery, M. (2017). Managing player workload in rugby union. British Journal of Sports Medicine, 51:421-427.

5) Nassis, G.P. and 
Gabbett, T.J. (2017). Is workload associated with injuries and performance in elite football? A call for action. British Journal of Sports Medicine, 51:486-487.

Gabbett, T.J. (2016). The training—injury prevention paradox: should athletes be training smarter and harder? British Journal of Sports Medicine, 50:273-280.

7) Hulin, B.T., 
Gabbett, T.J., Caputi, P., Lawson, D., and Sampson, J.A. (2016). The acute:chronic workload ratio predicts injury: high chronic workload may decrease injury risk in elite rugby league players. British Journal of Sports Medicine, 50:231-236.

8) Hulin, B.T., Gabbett, T.J., Caputi, P., Lawson, D.W., and Sampson, J.A. (2016). Low chronic workload and the acute:chronic workload ratio are more predictive of injury than between-match recovery time: A two-season prospective cohort study in elite rugby league players. British Journal of Sports Medicine, 50:1008-1012.

9) Hulin, B.T., Gabbett, T.J., Blanch, P., Chapman, P., Bailey, D., and Orchard, J.W. (2014). Spikes in acute workload are associated with increased injury risk in elite cricket fast bowlers. British Journal of Sports Medicine, (in press).

10) Hulin, B.T., 
Gabbett, T.J., Blanch, P., Chapman, P., Bailey, D., and Orchard, J.W. (2014). Spikes in acute workload are associated with increased injury risk in elite cricket fast bowlers. British Journal of Sports Medicine, (in press).

Back Pain Rehab: Axial Isometric Loading

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While spinal flexion can be a common aggravating motion for people recovering from squat or deadlift-related injuries, axial loading (or vertical forces through the longitudinal axis of the spine) should also be assessed as a potential pain-reproducer during the physical therapy clinical examination. Individuals who fall into this category may feel excessive compressive-like pain simply when setting up underneath a loaded bar due to the vertical loading forces upon the spine. Depending on presentation, one may need to consider the possibility of endplate vertebral fracture(s) and to refer out to the appropriate healthcare professional if necessary for further diagnosing. However this is most commonly seen in postmenopausal women, people with osteoporosis, the elderly, or people who've experienced trauma or infection (PMID 23251117). _ You can see from some of my previous posts that I'm a fan of isometric exercises using a barbell as early stage rehab work for powerlifters and weightlifters. They're specific to the demands of their sports by enabling them to generate muscular, isometric tension in relevant positions which can also provide an analgesic effect (PMID 29163981, 25979840). An isometric, axially-directed force through the body can be performed either in the setup when one is preparing to wedge himself underneath the bar, or as a progression, when the lifter is arising out of the hole and is ready to re-acclimate to this bottom position. Just place the J-hooks in the desired position and squat upwards into them, while simultaneously pressing your feet hard into the ground. _ As I mentioned in my previous posts I encourage lifters to breathe through these isometric contractions so as not to rely on Valsalva-generated intra-abdominal pressure for strength, but to rather seek it out through muscular tension alone.

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