Scot Morrison - Energy System Development & Tissue Specific Rehab (Consultant Sports Physical Therapist)

Hi guys it's Andy Mcdonald, Physio and Strength in Conditioning Coach and welcome to the inform performance podcast. On stage show we have Scott Morrison. Scott is a board certified physical therapist who specialises in high performance sports medicine. He has experienced working and consulting across elite sport and tactical communities and he currently works within special operations. Scott serves as the chair of the AASPT sports performance enhancements SIG and is pursuing a PhD under Franco and Pellizari. In this episode of Scott we'll discuss his academic work on psychometric properties and we'll be spending a lot of time discussing energy system development and tissue specific rehab so lots to unpack within this conversation. This episode has been sponsored by VOD Performance Makers of Forstex, the world's fastest, easiest and most powerful dual force plate system. Forstex can help you to analyse neuromuscular strength, performance and imbalances in your athletes. With an incredibly simple setup and intuitive software, Forstex automatically detects over 15 common force plate tests and analyzes them with a single click, helping you to collect quick and accurate insights on your athletes. To learn more head over to our sponsor VOD Performance.com. Inform Performance is a proud partner of Humac Norm by CSMI. One of the best and simplest ways we can resolve a limb symmetry strength deficit is simple isolated joint training on the Humac Norm Isaacanetic system. Isaacanetic resistance allows the athlete to stress their muscles at full capacity throughout the entire range of motion. Supplement your athlete rehab or performance program with a highly effective and data rich machine by using the Humac Norm Isaacanetic system by CSMI. To learn more about the new humac norm and refurbished machines, visit humacnorm.com. You're listening to the Inform Performance podcast with me Andy Mcdonald and here is today's guest Scott Morrison. Hi Scott, welcome to the show mate. You've been a highly suggested guest, so it's great to finally have you on the show for a chat. Awesome, glad to come on, thanks for asking me and hopefully whoever's repeatedly suggesting that enjoys it. A few people have asked, so you've definitely been a well-recommended person. Just to get into things, would you be able to outline your career background through to where you started and where it's got you today just for context? Yeah, so previously I worked a lot of manual jobs, construction, logging, et cetera, up until I went to college and majored in exercise science, I guess, with emphasis in kinesiology. During my time there, I started working within the domain of physical training, training people at the gym. Lots of mistakes made during that time, like spending way too long teaching people how to do a single exercise. From there, moved on and mostly worked within strength and conditioning, high performance, training of general population, and more broadly health-based intervention, so population level type things. I ended up running a medical fitness center in South Florida for a while while I went back and did PT school. Got my doctorate in physical therapy about a decade ago now and at that point switched over to more of the both performance but also than the medical side. Within there, I had the opportunity to work on a variety of different settings from general outpatient to running my own practice, where predominantly sports, consulting, education, did a stint with the professional referee organization, as they're ahead of medical services, and then for the last while been working within high performance tactical communities. Very good mix and very broad as well by the sounds of it. When we caught up on the phone the other week, you mentioned you're doing a PhD as well. Is that something you're able to discuss and kind of outwardly looking at? Yeah, so it's still process of, you know, the learning never ceases, but the broad spectrum or the broad question is really coming back to my interest has always been in decision-making and decision-making requires input. We need a feedback loop, but when is feedback feedback? A lot of times if you think of things like applied kinesiology, you're doing the process of having that concordant sign that helps dictate what you do, but you're basing it off of a metric that does not actually map on to the construct that you care about. So test and measurement has been a big thing for a long time for me, started off actually using Vald when it was four sticks was my first step up from just doing it all in Excel. And then as you start going deeper into these things and you start understanding a little bit more what you're doing, you keep coming back to the idea of, okay, what am I testing? What am I measuring? And that one thing led to another, and so the current process is really around psychometric properties of testing, especially human force development, and decision-making clinically and within high performance based off of what those tests tell us. So that's kind of where my head's at right now. When you say psychometric properties, what would that mean to how that function in like an applied setting if somebody in a team sport perhaps is listening now? How would that kind of relate to what they do? Yeah, so everybody knows some of, you know, the basic terms of validity, reliability, et cetera. And we have this tendency to believe that we purchase a piece of equipment that's valid and reliable, whereas the reliability is on us in our testing process. That's the key. There's no tests that's for force plates aren't necessarily reliable. The tests that you do on the force plates reliability comes with a error measurement, which is largely based off of what you do, as long as the piece of equipment has been calibrated. And this is why you don't need to validate or, you know, do a reliability study on every piece of equipment. You just need, we know what it measures. We know the rate that it measures at. And then we apply that to the construct that we want to measure. That's where that reliability concept comes in. And it's the ability to get a piece of information and understand how much of that information represents the construct that we care about and how much of that represents the error that we've placed on it. Then validity starts becoming, it's not necessarily a valid test. It's a measure of, we can, I think, validity is best thought of as the decision that we make with the data. Did we make a valid interpretation to the individual in front of us? So whether or not the information we have is representative or reliable does not necessarily then mean that it's also valid just because it's been cross reference with a gold standard. And then I guess one of the big last ones would be sort of responsiveness, which can be thought of almost as validity over time, or more along the lines of whether or not the instrument is able to detect a change in the thing that we care about. So we may detect a change, but is that change actually representative of what we care about? And I think, uh, Turry and David and their book Measurement and Medicine, I believe, is where they did this quote that I really like was along the lines of, since the goal of medicine is the resolution of the problem that the patients presenting with, then tracking changes in that problem over time become very, very important. And that's, that's basically if we think of psychometric properties of testing are kind of around that idea. Yeah, I love that. I think it's, I think you've probably seen this as well, but in an applied sense, you know, a program can sometimes mistakenly for no purpose for reason have to include a squat or a testing battery has to include a CMJ. And I'm not saying that you shouldn't have a squat or a CMJ, of course, but it's kind of, you know, you get used to seeing the process. And then in your process, you almost include things for the sake of that common things to include rather than what do you actually care about? Yeah, yeah, you get more involved with the ritual than actually answering the question that you care about. And it's almost three steps. First step is identifying whether or not the, the way that we query the individual gives us a quantity that maps on to the thing that we care about. So let's say in this case, strength. So if I want to measure strength is what I'm doing, giving me a actual decent, you know, representation of that. Now what we're getting is force output during a specific task. So then we have to identify is that force output, which we're now representing with this number. And we know that it's a rely, we have a reliable process in place to pull that number out. But does that number actually tell us anything about the construct of strength? Because strength is a fairly broad topic, right? It says we can think of it almost like a higher order construct. It's, when we tell someone, this is a strong person, everyone will be shocked if that person was only able to produce high levels of force during a, as a measurement dipole, but then would struggle with other tasks in a general environment like they can't help you move your couch. So we have this idea of strength as a broad construct, but then our, our method of measurement might be an isometric that pull, which is looking at the ability to produce peak force in a very specific setting. So that's partially mapping on to that general idea of strength. And then the last thing we have to care about is does strength matter for the outcome that we care about? Because in sports medicine, especially, most of the time strength is just a proxy for their ability to perform, right? Their ability to go out and do the thing that they do. So we, we almost have those three steps to ensure that the decision that we're making based off of the tests we did is actually related to the outcomes that the individual in front of us cares about. Yeah, no, perfectly putt. We had a chat, a very short chat last week about tissue specific rehab and testing. Would you be able to talk us through your personal considerations and approach to this? Firstly, kind of how you assess or praise tissue health and then based on that, how do you then focus rehab? Yeah, that's a hard one because appraising tissue health is most of the time in a general clinical setting is based more on heuristics and proxies such as, you know, pain. Pain is not necessarily representative of the tissue state going in a detrimental manner. So think of bone stress injury, for instance, we know that there are procedures and decisions we can make prior to bone stress injury usually around training and how we scale and dose that training to help prevent that bone stress injury from occurring. But we don't in a clinical setting usually identify that till after it's a problem. So I think upfront that's the biggest thing is first of all tissue health is predominantly based off of best guesses unless we have access to something like ultrasound or other forms of imaging, which gives us more information, but then sometimes that information becomes problematic because, you know, somewhat let's say 10, for instance, 10 and a 10 and a path of changes is not always predictive of the outcomes that we're trying to avoid. So there's all these considerations we have to care about. So I would say clinically most of the time I'm operating underneath a dual estimate of projected future problems based off of what their training program is looking like or addressing an issue where things have already occurred. And so then once the issue has occurred, that's where we start looking into just good clinical decision making. A good example is knee pain. And, you know, it's a very generic aspect, but we can get anterior knee pain from a quadendinopathy. We can get it from patellar tendon. We can get it from patellar femoral joint pain. We can get it from plyco. We can get it from a lot of things that can be creating that anterior knee pain. And it is somewhat, I think, popular maybe. I don't know if that's the right term, but it's definitely a narrative that we hear a lot is as deep pain anterior knee pain. Just treat it. Well, I'm going to treat patellar femoral pain differently than I would a patellar tendonopathy if I'm looking to treat the tissue. So if the tendon we know we have basic processes of loading, whether or not we use isometric or anything else, it doesn't really matter. It's more about are we applying enough strain to the tendon cyclically out of frequent enough basis in order to enact or create that change that we're looking for. Whereas patellar femoral pain is largely about training around the painful area to maintain some of the capabilities and then maybe doing some created exposure and progressive overload within that range of motion that's painful to either decrease sensitivity and or hopefully create some cartilage adaptation as well. And then both of them we might be looking at maintaining or regaining some of the knee extensor torqued capabilities of the muscle if we've had some atrophy over time. So all of a sudden anterior knee pain we might be doing the leg extension, but it might be end range flexion to predominantly work on the muscular adaptations and then doing some isometric holds or some short arc work within the painful arc and then doing some isometric work on the outside if we also or for a tendon type issue. So that's more so how I'm taking the approach with the very very clear understanding that just because we're doing this doesn't mean that that's necessarily what the problem is and just because that may be the problem isn't necessarily the reason why they're dealing with the problems that they came to you at. But I tend to say as a high performance therapist my role is performance outcomes and if we train for high performance we're usually also dealing with most of the tissue specific aspects or injury I guess I should say injury prevention aspects and so I tend to view this a lot more in the domain of a dynamical system where we're going to have a task that the body is trying to accomplish and most of the time if we give our movement system the ability to do the task without loading through the problem it's going to do so because the goal of our body or the goal of that that we face the athlete with is to accomplish a task. And so for tissue specific training I would say the biggest overriding theme is really understanding biomechanics sufficient to constrain the task to ensure that the movement that we're doing is forcing the load to go through that tissue so that we create the mechanical transaction and basically get the adaptations that we're trying to get sort of a roundabout way of answering it but yeah it's a messy thing I think. No no I appreciate that and I think I really appreciate that you said or you considered both you know the performance in the task but also the tissue because I mean I don't know about you but I think sometimes clinically in you know PT's or not PT's you know rehab professionals can be a little bit linear in going I'm going to address you know the clinical problems the tissue and then later on I'll do the performance and return to play if that even ever gets done versus you know I think like you know a classic case might be someone has a hamstring injury but whilst you're rehabbing the hamstring tissue you can also from a performance and task perspective rehab the calf and quad so they can control ground reaction force and you know there's loads of other contexts but I think I don't know about you but I think I often see clinicians do A then B then C but in reality there's separate streams that can be worked on at the same time. Oh absolutely and you know not not to only point fingers outwards there's plenty of times where I've reviewed my notes and been like ah damn it I should have done a better job of addressing these impairments or I test someone and I'm slapped in the face with oh yeah this thing is deteriorated and I should have been addressing it and for whatever reason you know it's hard to do a good job because there's so many different streams of different things coming in which is where it's kind of having checklists and flowcharts and understanding the KPIs that you want to sort of refer back to I think is hopefully what prevents us from making those mistakes as a career as opposed to occasional. Yeah I think kind of regardless of who you're working with or where you're working I think time honestly becomes the biggest difference or busyness becomes the biggest difference of like how good a job you do it's not necessarily whether you can and it's being from personal experience. If I've got loads of time it's way easier to plan and set reminders for different benchmarks and things that you need to include and do versus if you've got a ton of patients or you've got a ton of athletes it's a lot harder to zoom out and map out the process clearly. You know I think we we talk a lot about force capacities especially at the moment in current times which is of course you know one aspect is a quality of physical capacity in rehab or in performance. What do you consider around energy system development in rehab? Oh yeah that's a fun one. So ultimately we have to remember ATP is the currency of the body. Force production requires ATP. So fundamentally that energy system is not this secondary thing that occurs outside of the scope of the production of force it's just that we usually don't find in those one off type tests that energy systems are the limiting factor and that's I guess kind of how I tend to view this sort of similar to like I was saying with movement if we're looking at the task accomplishing the task is the goal then however that's accomplished that works if you're told the person to squat and they move the bar from standing down and then came back up with it they've accomplished a squat whether or not their knee sensor mechanism or their killies or they use more of a hip to like all of those things are secondary to accomplishing the task but then if we break it down and we actually start looking at all right why is this how do we improve this that's where we have to actually look at what are the constraints what are the things that are potentially limiting us from performing well and in the vast majority of sports and tactical settings your ability to express your skill is limited more by the fatigue than it is by your strength most there are some people and there are some sports we're getting stronger is linearly tied in but most of the time skill training and then the ability to stay fresh and and have a large percentage of your force production output available to you is the key so that's where the energy system is something that we have to definitely bear in mind especially if we are removing an athlete from the day-to-day activities that usually maintain that so if we're pulling somebody out of practice we're pulling someone off the line whatever it is that we're having to do because of the injury by that action we are taking ownership of their physiology at a much larger level and so an understanding of training rates and detraining rates becomes just vitally important to me in this realm because again we're treating a human who performs in whatever their sport or task is we are not treating the knee and I mean we're all in medicine in particular is really really guilty of this whole idea that the knee walked in the door and the knees better now but we've now had six months of aerobic system detraining or we just tell the person I just you know go go ride a bike or something and or their return to running program is all based off of the knee tolerance and the problem we have is the knee or the Achilles or the shoulder right depending on like whatever the thing that we are treating that is imposing a much larger constraint on them than what their energy system is limited by so I the analogy I'll typically use is you're going for a hike up a hill with some friends and someone brings their kid it doesn't matter how good of a shape everybody else is in you go at the speed that the kid goes and that's what the injury does for all of these other systems and so if we just return to run based off of the tolerance of the joint that we're treating that's great but running is no longer a cardiovascular exercise running in that point is an Achilles tendon exercise if that's what we're treating which is good and needs to be addressed but now you have this energy system that is not being stressed and so it's detraining and I think that fundamentally from a rational or thought process is what's led me to okay this is definitely something we need to look at and then you can go into all the nuance of how you do it and um all those sort of things but that's that's why I think it's valuable that's why it's something we need to bear in mind the same with every other aspect of the body physiology is not static it is a reflection of what you have told it over the last little while that the world is like right so your body is always making predictions and John Kylie who I believe you've had on here before talks a lot about the sort of predictive processing aspect from some of these non-specific effects but from a specific effect as well we're we're telling our body through stress what the world is like and it adapts to that so if we lie to our body repeatedly over time and then we dump on it some oh no you're actually going back to this high level of activity well it's prepared for a world that we told it was out there instead of the one that was out there so fun like when I'm looking at the like what is the thought process here it's how can I ensure that the world that this organism is going to inhabit is reflected in the training that they're being exposed to throughout there and we cannot do that accurately without considering the various energy systems you know kind of beyond crediting that this is important is energy system development something that you in different injury context assess or is it something that you're kind of prophylastically prescribing oh no yeah I mean I I find it very hard to make decisions without kind of having a benchmark of some kind I think one of the easiest ways to do this from a clinical setting is using maximum aerobic speed it's just a very easy time trial six minutes all out on whatever the thing is that you're trying to work on and then you utilize that to prescribe training loads it's great because so for instance had someone recently with Achilles syndesmosis injury and need to maintain high level of aerobic training so we started off with a non loaded maximum aerobic speed test and then we used that to give him so whatever his you know four to five hours a week of zone one zone two is the popular you know the way to phrase a cardiac output depending on who you talk to the phrase but basically lower levels of total energy expenditure however at a high enough level to where we're getting central adaptations and I really like the the book physiology sports performance I believe by McDougal and Sale is a just a phenomenal one and that's kind of the three big buckets they'll talk about central adaptations peripheral adaptations and then you can think of your anaerobic power and capacity type as long as you're addressing those clinically you don't need to necessarily replicate small-sided games and especially for clinicians who aren't on a team that's almost impossible to do however you can replicate sports specificity in this setting is replicating the energy systems that are needed in the sport not the work rest ratios of the sport and I think that's where we get things confused a lot the sport itself is the skill just like that squad I was talking about earlier with the movement thing and you have to do some of that but that's mostly skill work the way that we create adaptation is to remove the organism from the task and to constrain the stress so that it goes and is directed to the area that we want to see adaptation and this is why when you you know you can start whatever the sport is and you will get fitter up until a point and then at that point you have developed enough to where your body has enough compensations around it you can strategize well enough you're not going to get that much better just by doing the sport you remove yourself from that sport and you still go into let's say you do a block of heavy lifting your force output will go up and then you can go back and reintegrate that higher level of force back into the skill of the sport that you care about energy system is the same way understand what the demands of the task are and for the most part a big aerobic engine is a very very valuable thing and we can get that with relatively low levels of effort so for instance with the guy I was talking about that's where we started with just a generic low level you're going to accumulate a certain I'm I usually prescribed based off of time not distance because distance makes people try and get done sooner whereas time it doesn't matter how hard you go at the same amount of time passes so if I most people are much better at sticking to the exercise intensities that I'm looking for with that as he progressed what we started doing is we just rotated in so in that initial phase the running type exercise was Achilles specific so we were just doing brief bouts maybe some sled work is what we started with and then going into some easy uphill walking stuff that was all specific to the calf complex not energy system the energy system then once he was tolerating let's say incline walking on the treadmill incline walking on the treadmill became our base training and then since usually I'm aerobic training we're starting immediately and then I start rolling in some of these higher intensity type things that was then the bike the offloading so we just do a mass test on the new thing that we're going to utilize and he starts using that so over time we just progress stage by stage the energy system prescription was pretty much the same that I would use with anyone whether the injured or not we just rotated modalities through until finally we're back to doing sprints for some of the higher intensity work so energy system training is the same the modality is usually what we're fluctuating around for most of the orthopedic sports injuries obviously it's different if you have a cardiovascular issue but yeah I would say absolutely you measure it I personally utilize lactate testing I recently dipped my toe into the near infrared spectrometry with the moxie monitor I'll do heart rate type test where you know time trials a drift test there's a lot of different things that I'll do a yo-yo intermittent fitness test for some of my field and court sports when I was working with them more or the 30-15 if I have room for it so yeah absolutely testing is happening my prescription is based off of the testing but the the process become the process is similar the test are similar the modalities change to reflect with the orthopedic issue is not the constraint that that makes sense yeah completely and yeah very far answer one of the things I want to kind of dig into within that if you don't mind is you know let's say the example of the Achilles in a running based athlete you when they can tolerate walking or running can of course then from a tissue perspective build in energy system type modalities like walking or running because they can do it what do you do or do you at an earlier stage test them out in you know a non-lower limb loaded format so skier hand bike do you sort of look at energy system development at the very earliest stages even though it won't be in the same half of the body does that make sense yeah yeah absolutely so yeah the maximum aerobic speed I will do on whatever it is that we've decided to utilize because when especially in an in season or a trained individual you're the energy systems not injured and you're trying to maintain those adaptations so when we think of central adaptations we can get that with a wide variety of training the specificity of the lower limb injury yeah we're going to have to redevelop the tissue to tolerate the running eventually but to maintain left ventricular size blood plasma volume etc etc that is all going to be something that we can maintain through whatever it is so for instance if I'm using maximum aerobic speed again the reason why I like it is it's just quick and easy and you can get a lot of information out of it if I'm using that I'll say all right what do you have access to so for instance let's say we've determined that this is somebody who's not going to be able to tolerate much lower limb type things so maybe we do the air dime bike all right get on there goes hard as you can for six minutes and then we divide the either total distance or total watts depending on what we're prescribing by you need a total measure so that six minutes needs to be reflected in the total measure and then you divide that total that they've accumulated by the time and then you can prescribe whatever it watts per minute or miles per hour whatever it is that you want to do and usually we will take that maximum aerobic speed and multiply it by the interval that we're looking for at whatever percent so maybe if some of our threshold work if we do like a 30 second on 15 off times 13 which is a relatively popular one you can do that like three or four rounds we might do that it let's say 80 percent of maximum aerobic speed for the 30 seconds so whatever the modality is and then when that we switch let's say we started with the aerodine and then we switch to now something like the let's say they go they're going somewhere for a while in the ellipticals what they have to do we just redo the maximum aerobic speed test on the elliptical re-prescribed based off of the same programming so the modality we just re-look at now again that's not all I do but if we're looking at the sort of bare minimum I think that plus a generic get in and accumulate time at a lower heart rate you know maybe if I'm making a general estimate one 15 to 135 ish again very very generic it's not going to be specific for anyone but you're it's harder to go wrong in that range and just accumulate time there that's a pretty easy split that's going to help you maintain a large portion of the adaptations yeah that makes a big sense this is going to be a little bit of a segue but I think given the sort of pragmatic nature of what you're looking at in your PhD I think you're the best person to ask I think year on year we get more technological advancements and research that comes out and it's I think easier year on year therefore to be more granular in our fault processes for performance or for rehab for you how do you kind of appraise when evidence is evidence and when we can then trust and make good decisions off of it does that make sense yeah um I'm still trying to figure that out so the large majority of the time the first step is when in doubt doubt understand to the limitations understand what you don't know and I think that that's really where it starts with for me it's better to recognize that you don't know something if we if we think of sense-making and the Kinevin framework is a good one for this that Snowden does and he talks a lot about sense-making which is sort of a we're probing we're responding we're understanding the process sense-making requires us to have a estimate of what's going on again this is all predictive we're you're making a best guess of a future state we approach a problem differently if we don't know what's going on then if we do an analogy I've used a lot is if you're going to your bedroom and the lights are out you walk around at a certain pace because you know where everything is if your partner moved around furniture in the bedroom before you went in you run into something you had high confidence but it wasn't reflected in reality and so you ran into a problem however if your partner tells you hey I rearranged the furniture when you go in either you're going to turn on the light or you're going to move much more slowly you're it's much more of a probe and then respond as opposed to a intervene and then probe or an intervene and then look for feedback so I think that step one is really that that understanding of what we don't know step along within that I think if we're asking about when is an evidence in evidence is an understanding of how detrimental point estimates are for continuous variables within medicine and the the ease of having this cut point and threshold in things that are not binary but are continuous a great example is cut points of symmetry right why is it the 10% is okay but 11% it's a problem right there's there's not this that's not how continuous variables work and so thinking of it more in a sense of probabilistic area under the curve likely less likely highly like right understanding those probabilistic or likely good based terms is a key aspect for this I think something that Frank O'Lean Plasari who's my advisor mentions that I think is a very good point is part of the reason why magnitude based inference did so well was because it spoke in that language and so it answered the problem that we're all trying to understand is how how do we make sense of this but that's a great example of giving the answer that we need to make a decision but based off of a metric that does not actually map onto the construct or does not accurately reflect reality so those are kind of the the fundamental discussions that we need to have and I think a good example is force plates right so jump test and you've got how many million different tests that have been rolled out but if you do these tests and you start looking and you look and you look and you start looking at your trends and how long does it take for things to stabilize you start realizing that something like a squat jump is a very challenging jump to get good data off of because everybody wants to do the little bit of the counter movement that's fine if you understand that and that's part of your thinking but if you believe that when you've told someone to squat jump the thing that they did was a squat jump I think that's where we start having some of these problems so sure we can slice and dice more and more and more finally however we need to roll everything back to the beginning and ask is the thing that we are having the person do giving us information that is reflected on the thing that we cared about another analogy I use a lot is we step on a scale in order to know how much we weigh the scale does not tell us how much we weigh the scale tells us the amount of force that's going through it and this is why everyone has had a friend who snuck a toe or finger onto the scale behind them to make them think they weigh a little bit more than they do that mismatch between what we believe our instrument is telling us and what the instrument is telling us is almost always where we run into the problems sure there's also the thing about don't jump up and down while you're on the scale there's also great to the reliability validity that we were talking about earlier I'm sorry reliability that we were talking about earlier is a key component validity is the thing here of is this number something that I can use to give a valid interpretation of that person's weight and that's going to be based off of your process and where you go so I think circling back to your question we've we've almost gotten enamored with the glitz and glimmer instead of just the basic boring I think a good way to think of this is validity is never finished it's a constant process of getting more and more information that maps more and more onto the construct we care about so that we get a better understanding adding more numbers adding more metrics adding more tests is not actually giving us more information it's just giving us more noise now it may be that some of these tests are very very valuable but we need to go through the process of understanding what is the construct we're trying to measure does the thing that we're measuring tell us something about that construct and then at that point we can turn around and then ask does that construct then have an effect on the outcome that we care about and I think this is where everything just needs to be real back and all of these things that are fun to do and need to great we need we need to keep doing pushing learning however just because it's out there just because it's an idea does not mean that we have certainty around it and just because it makes sense that the face value does not mean that the thing that we're seeing is representative of the construct that we care about and the change that we see is not necessarily reflecting change in that construct so that's everything to me I mean that's why kind of started with this whole question is let's dig down the first principles what is it that we have to understand before we can take the next step and I think that's the area that we keep getting ahead of ourselves on I think we I'm interested to hear your comments on this I think it's really easy to obsess over what you test for certain situation versus I think testing frequency is really overlooked and in the case of like let's say it's the ACL because it's really relatable for a lot of people let's say at a certain stage you're testing open kinetic chain the extension you might test it once program accordingly tested again if the numbers look good you may not do that test again you may by default just progress to close kinetic chain tests and then you have this assumption and look it's likely but you have this assumption that the second test result being improved hopefully was purely an only a result of the program and the rehab that you instructed and the person did completely neglect in the fact that there's a skill to testing and it's the second time they've done it there's a psychological part you know they're they have an engine in your testing for the second time they're probably a lot more comfortable the second time than the first time and there's lots of other things that play into it than just those tests and I think we we sometimes try and do too many tests but not enough frequency to them and let rip rip that apart if you may but I'm curious to what you think no I'm 100% with you the recently I was talking to Patrick Ward with the Seahawks and I was like I as time goes by I find less and less value in one-off testing I just don't know that it tells us anything and I the way I view this is exactly what you're saying we need to test as frequently as we would anticipate a change having occurred not to make a prediction about some future thing but to query the decisions that we made previously so for instance with with that ACL if we decide strengths should or strengths should change somewhere in a four to six week period so we're going to test every four weeks we're doing that to understand whether or not the interventions that we're doing are making the changes that we care about but just because we see a change in score does not mean that what we did created that change right we have regression to the mean on our side the fact that somebody had surgery as time progresses they will be getting closer and closer to their normal regardless of what we do so we have to say all right is the rate higher than the rate would be if they did nothing else we have to understand the difference in score what is the error of that first test and the second test do those overlap at all so is the change that we're seeing a reflection of the change in the construct so like as that quote I was talking about where if the if the goal of medicine or the goal of rehabilitation is to resolve that issue then we really need to track the change of that issue over time because that's the thing that we said we cared about so the difference in the testing is that a difference of the test is that a difference of the construct we care about is that a reflection of like you said the patient's comfort and confidence with the test is that a difference in how we queued our process so all of these things start becoming questions that we have to understand you can't just pull a standard error measurement out of a paper and then slap it onto your practice which is already two steps beyond what we tend to do a lot of times but your process may be very unless you're replicating the process that was done in that paper then chances are good that yours is going to be a little bit different I usually suggest that people and this is something I'll do when I go work with a new group we'll just do a test retest and look at what what is the standard error that we have so the shiny app that I made for estimating knee extension torque but you can do torque for any limb with it I just used data from a study that we did with about over over 50 individuals with a couple different test setups and I used that so that's the standard error that I used not because it's necessarily going to be the same one that other people do but I wanted to create a visualization of this error so I have a basically a plot of the likely true score around whatever the score is that you measured and that way when you can just visualize how likely is it that the test that I measured is actually hitting the benchmarks that I care about or is actually different is there actually an asymmetry how much overlap is there between the two so that was kind of the central theme for why I ended up doing that but yeah I 100% with you the key to all of this is not to do a one-off test to clear someone from return to play I have very very limited confidence that we're able to make any sort of prediction on somebody's re-entry based off of that but we can do is query whether or not the intervention that we were doing is create and maybe not maybe I shouldn't say is creating change but whether or not change is occurring in the thing that we care about and if it isn't then that gives us a sort of signal that we need to go back and change something about what we're doing with yeah I'm laughing at myself on reflection now having this conversation with you about the amount of times I've probably tested somebody for the first time on something as it relates to say force you're in an injury process and probably being quite quiet while they test you know encouraging a little bit and then working with them for say four weeks or whatever it is coming back to that same test and and screaming at them to produce a higher force and I'm thinking that it's fair that on the first time you know my queuing was quiet and gentle and nice and then the second time probably because I've invested so much time with them and doing it you you scream at them to get the highest score so I'm just I'm just laughing at like oh it's everything worth talking about that's an ongoing joke at most places I've worked I know currently there everybody's like oh you can tell when Scott's testing someone because I'm loud and I'm vocal and I try and always do it the same because that matters music whether music's playing or not makes it like there's all of these things make differences and it's fine we can't control everything but we should understand when we're looking at the the measurement that we got the number that came out on that printout is composed of a true score which is a relative to the construct we care about so strength in this case or forced output or torque whatever it is that we're saying we're wanting to measure and a component of measurement error and our goal is we can't eliminate the measurement error but we're trying to make that error as standardized as possible so it's similar each time and the more we can standardize that error the more likely it is that when we see a change score that change is actually coming from the underlying construct as opposed to something different about what we've done I want to I'm aware of time and I really want to squeeze in a nosy question selfishly from my perspective of you know you you come from a dual background of you know strength and the clinical background as well you know you know you're doing a PhD in a very pragmatic topic what outside of that PhD what what are you looking at what are you curious about at the moment I mean obviously there's always papers and stuff that we're reading but what influences your fort processes what where do you turn in by the oh man that is so I am a very very avid reader have been my whole life I tend to find that reading outside of my field brings a whole lot more positive feedback it's almost like we aren't the only ones who have ever faced these problems and other fields have done them much much better for a large span of time so specific areas of interest I am doing a lot more with energy system training or the especially the aerobic system just because of my current role and that that's a huge component of what I'm doing not that we don't also do the anaerobic stuff but the the aerobic is an area of interest to me at this point Bayesian sort of thought processes statistics but also reasoning is a massive massive influence on me and understanding or I probably not say understanding but influencing or flavoring how I view the world in general communication scientific communication but communication in general more and more the idea of telling your patient's narrative forward with them to ensure that it's something that resonates with them I think you know this is the common thing that you'll hear from a lot of people is as time goes by you you worry more about communication than you used to and maybe a little less on the specifics of how you how you wiggle the way to round or whatever the case may be those those are some of the bigger ones there's always some fundamental underlying aspects of decision making theory is always a huge component for this I find military strategy and military decision making to be a really good one as well as business because both of them tend to have very high stakes with more clear if you look for it output on whether or not you were successful one of the biggest problems in sports medicine is we can kind of shrug our shoulders and always find 50,000 reasons why what we did wasn't at fault and something else was but then more than happy to you know I've done this myself planet yeah oh that that came out well that's because of what I did that didn't come out well that's because you know we can't predict all of these such things so there's there's that decision making just to me as a as a fundamental component there but yeah causal reasoning those those sort of things are underlying definitely influencing a lot of what I do now thank you and it's yeah definitely food for full where can people find you and is there anything that you want to plug and kind of draw attention to that that relates to what you're up to oh I'm not big on plugging things but I so Twitter is typically where I interact the most as within professionals SCOT M-O-R-R-S-N is my Twitter handle Instagram is more where I dump content things so I'll obviously interact on there but I find that the Twitter is easier to have public conversations Instagram tends to be more private messages that where we have conversations that one is physio underscore praxis is my handle I do have a website physio praxis dot c o or scotmorson dot com the both lead to the the same site I would say if you're a sports med practitioner I am also the chair of the American Physical Therapy Associations the sports academy within there I'm the chair of the sports performance special interest group so we do have a pretty vibrant community if you are an APTA member definitely check that out we have a lot of content that we put out free for all members and if you're not a member the Instagram page on that we do produce all of our we have of podcasts and things like that and we make infographic so a lot of good user friendly type things on there I believe it's a a spt if you look at my Instagram I'm blanking on what the Instagram handle is but if you look at mine you'll find that there cool thanks mate and no it's been a pleasure to host you and get to know you and yeah thank you very much for your time today no it's a pleasure to have the opportunity to come on I appreciate it thank you