So Brian writes really long questions. Thank you, Brian, for your contributions. Don't change the thing. I like what you're doing because it makes for a great setup. Just hang in here as I read through this. So with a client with an inhalation axial skeleton archetype, which would be typically a narrow infraternal angle for those of you following along, I want to use an exhalation strategy with my client because they are biased towards an eccentric pelvic diaphragm. So I use a box squat. So he's making reference to the box squat video that's up on YouTube. I would use a box squat at 90 degrees and coach them to explode off the box with a strong exhalation concentric strategy for an exhalation axial skeleton archetype with a wide ISA. I would promote an inhalation strategy with my client. Use a deeper box squat, promote more yielding and descending pelvic diaphragm. So thanks, Brian. In general, yes, but the first thing we have to do is we have to decide what the goal is. And so if my goal is to maximize the variability within the system using my movement system as my proxy measure, then your assumption is correct with a few caveats. So I could bias someone with a high box squat towards an inhalation strategy as well because through that middle range, somewhere around the sticking point is where you're going to be biased towards a more nutated position, a more concentric pelvic diaphragm. So your understanding of where to place this person that needs a more concentric pelvic diaphragm strategy or an exhalation based strategy is correct about that 90 degree angle. But remember, we can bias them above or below depending on the needs because there are some people when we do put them on a low box, from a technical standpoint, they're using a spinal flexion-based strategy, which is what we do not want to reinforce. What we're looking for in the lower box squat is the ability to counter-nutate, which is not the same thing. And so I don't want to create that kind of confusion because I think a lot of people don't distinguish between spinal flexion in a counter-nutated position because the lumbar spine does move backwards. It reduces its lordosis when you counter-nutate versus the spinal flexion above the pelvis, which we do not want to utilize because it does put excessive load on those posterior spinal structures whereas the counter-nutation really doesn't do that to any great degree. So Brian, I think you are on track with that. I think your understanding is correct, which is awesome. Now, so Brian asks a second question. And again, bear with me here, Brian likes to write a little bit. Is a compensatory inhalation strategy a strategy someone uses when they are biased towards exhalation and compression? Absolutely. And so we'll talk about here in just a second. Let me finish what you wrote here.

With a client with an inhalation axial skeleton archetype, which is typically a narrow infrasternal angle, I want to use an exhalation strategy because they are biased towards an eccentric pelvic diaphragm. I would use a box squat at 90 degrees and coach the explosion off the box with a strong exhalation concentric strategy. For an exhalation axial skeleton archetype with a wide infrasternal angle, I would promote an inhalation strategy. Use a deeper box squat, promoting more yielding and descending of the pelvic diaphragm. In general, yes, but we must first decide the goal. If the goal is to maximize variability within the system using the movement system as a proxy measure, then the assumption is correct with a few caveats. I could bias someone with a high box squat towards an inhalation strategy because through the middle range, around the sticking point, you'll be biased towards a more nutated position, a more concentric pelvic diaphragm. The understanding of where to place a person who needs a more concentric pelvic diaphragm strategy or an exhalation-based strategy is correct at that 90-degree angle, but remember we can bias them above or below depending on the needs. Some people, when placed on a low box from a technical standpoint, use a spinal flexion-based strategy, which is not what we want to reinforce. What we're looking for in the lower box squat is the ability to counter-neutate, which is not the same thing. I don't want to create confusion because many people don't distinguish between spinal flexion and a counter-neutated position, as the lumbar spine does move backward, reducing its lordosis when you counter-neutate, versus spinal flexion above the pelvis, which we do not want to utilize as it places excessive load on posterior spinal structures, whereas counter-neuteration really doesn't do that to any great degree. So I think you are on track with that; your understanding is correct, which is awesome.

Watching all your videos with great interest, I'm trying to grasp the big picture of inhalation, expansion bias, exhalation compression bias, and the compensatory strategy one would use when they have either exhalation or inhalation bias. So let's talk about the very first compensatory strategy that's available. So if I am exhalation biased, that is due to physical structure, which will eventually hash out on some level. But for now, let's just say that you're going to have somebody that's going to be exhalation biased or inhalation biased. So if I'm exhalation biased, I have to figure out a way for me to breathe in against that strategy. And so let's talk about the infrasternal angle a little bit, because that's where this infrasternal angle stuff gets really, really interesting, because it is the first and the easiest way for us to determine what the compensatory strategy is. And it's probably the first and most important compensatory strategy in the human because it influences the capabilities of the thoracic diaphragm to allow us to breathe in. So if I'm exhalation biased, I would normally have a down bucket handle position of lower rib cage. But what has to happen is I have to be able to breathe in some way, shape or form. The first compensatory strategy is to allow that thoracic diaphragm to move. So if I'm exhalation biased, I cannot descend that thoracic diaphragm unless I eccentrically orient the abdominal musculature, which is closing down the bucket handles. So I will release that. I will eccentrically orient external oblique as an example to allow the ISA to open, and this allows the diaphragm to descend in someone that is biased towards exhalation. If I am inhalation biased, I have to figure out a way to exhale. And so I will use the musculature that would close the ISA and pull the bucket handles down. And so the first compensatory strategy, again, that's easiest for me to evaluate, is the lower rib cage because that's where the greatest capability to compensate is. And so as they exhale and they close the ISA with the external oblique, that allows me to exhale against that inhalation bias.

I was interested in the above post, never seen the exercise before. Do you think you could break down and explain in more detail what the exercise is doing to improve the shape of the thorax and the pelvis? And would you perform this on both sides? So what we were doing with the long strap, and again, just go to what's that strap, those guys apparently are doing really, really well. I hope we've contributed to their success. By wrapping the strap as it's demonstrated in the video, what we're doing is we're encouraging a certain type of thoracic activity in regards to the muscle activity and to the expansion capabilities of the thorax as you breathe. So we're actually providing a leading resistance. So this is a very PNF-ish kind of a strategy in regards to the way the strap is organized. And so what this will do, it will create a lateral compression against the rib cage, which closes the wide ISA and creates an anterior posterior expansion as we breathe in. So we're driving upper extremity motion. We're using a compressive strategy, a manual compressive strategy on the thorax with the strap. We're driving breathing strategy that will also enhance the reshaping of the thorax. And then we're driving those mechanics down into the pelvis. Then we superimpose the stepping strategy on top of that, and we're actually reshaping the pelvis in that regard as well. And so we're getting a really, really big bang with this type of an activity. But that is in a nutshell why that setup was as it was.

Dana asks, can you explain spinal and pelvic inhalation and exhalation in reference to client position strategies and exercise choices? So, Danny gives an example. So if you're elevating the heels for those with clients who need range of motion and more inhalation strategy, what modifications do you use for clients that are more inhale biased? So I'm confused with the foot position. If you supinate your feet using an inhalation strategy, and if you're proning, are you using an exhalation strategy? So simply by asking your question I think you actually understand what's going on here. So if we do have somebody that we need to bias towards inhalation, what we want to do is we want to use a heel elevator or a more supinated foot position because that is an inhaled position of the foot, so you're actually correcting your assumption. And then we would use a more pronated or a propulsive foot to promote an exhalation. So we can actually do this. We can bias this in any number of ways. Even with the heels elevated, we can bias you back and forth between an inhalation and exhalation strategy just by queuing where we're going to put the load through the heel as to whether we're going towards the medial heel or the lateral aspect of the heel. So if we were doing, say, a toe touch progression with heels elevated, that would bias this towards an inhalation strategy, but we could also promote some element of exhalation on top of that depending on the timing of the breath cycle and the movement that we're trying to address. So I think you have actually a really good understanding simply by the fact that you asked the right question. So Dana continues, Can you also relate public diaphragm mechanics to the cue? Pretend like you're holding in gas and when to use that cue. Dana, I have never, ever used that cue. Don't really know why I would want to use that cue actually. The concern that you have there is the interpretation of the client, because when you ask somebody to do that, there could be a number of strategies. I think what you're getting at is you're trying to queue the public floor to do something. The concern, though, when you talk about holding in gas is that you may actually unintentionally have someone that utilizes a more superficial strategy. So now we're going to influence some of the superficial external rotators or even some of some of Glutmax. And that's probably what we don't want because what we're going to do there is we're going to create a more of a compressive, externally rotated strategy through the musculature that is below the level of the greater trochanter and that might not be what you're actually looking for when you're trying to recapture the capabilities of the pelvic diaphragm.

So again, I don't like to use that type of a cue because I just don't know what kind of a strategy that I'm going to get. In fact, many times, we actually have to cue people out of that strategy to restore the full movement capabilities of the pelvis and the sacrum to coordinate with the breathing cycle. So again, I don't use that cue at all. But I thank you very much for those questions. Those are really good questions, Dana. So my next question comes from Alexa. She's a physiotherapy student in Scotland. So I'm about to graduate and will soon be entering the workforce. Congratulations, Alexa. You have mentioned in some of your past videos, important fields of science that should be considered in PT practice such as dynamic anatomy and physiology. I was wondering what fields and areas of science you would recommend an entry level PT to study and read. Additionally, do you have any advice for a new PT about to embark on this epic journey of starting in the field? So my biases in regards to the sciences that you're going to use are going to be more towards the physics side of things. So when we think about everything that relies on first principles and how we move, when we talk about pressures and volumes and fluid shifts and gradients and things of that sort, that all comes from physics. So the better that you understand that as a foundation of everything that we do, I think the more logical everything will start to seem. Superimpose that with the dynamic anatomy concept. So understand the foundations of how you evolved embryologically. So knowing where you came from is a phrase that I use a lot with the Padawans. And so you have to learn how to capture the meaningfulness of the anatomy with the underlying understanding of the physics involved. And so I think that that's where our thought processes really need to go. Rather than looking at the structural reductionist model that's typically taught in physical therapy school, I think that understanding that we are morphing, we are shape changing versus a series of levers and pulleys that behaves in this Euclidean geometric manner, which doesn't really apply, because when you look at the forces, the forces probably aren't realistic. If you look at where we came from, going way back from the evolutionary perspective, if we think about how we evolved from a single cell, the principles would have to be the same even on this macro level. The thing that we understand about complexity is that it started from simple rules and we just repeat those simple rules. I would say that spend your time understanding the physics of how we move. Look at how fluid works. Look at how gradients influence how those fluids shift, and that should be the foundation of your thought processes and then superimpose the dynamic anatomy. So learn the anatomy in a context rather than looking at it as we would a cadaver. Look at this as a fluid model, and I think that that's going to provide you a much more useful model in the future. So I wish you luck. The thing that I would also encourage you to do is get really good at what you do first. So spend a lot of time learning, spend a lot of time practicing. You're going to fail a lot; it's important that you fail, but you fail safely. You never hurt anyone, but it's important that you fail. And then I would say you need to find a mentor, someone that can lead you, because there are elements of understanding that can't be written down; they can't be expressed easily. This is what we call tacit knowledge, and this is what you acquire from a mentor, from experience. And so this is where your focus needs to be for the next three to five years. And by then, you should start to get better at determining from a probability standpoint what would be the best course of action. This is how you're going to get good as a physical therapist. So hopefully that provides you a little element of guidance in this regard. And by all means, keep asking questions. Always ask questions and try to answer them yourselves and then seek out the answers from other people and other resources. But keep the questions coming towards me. I'm happy to help. I love working with students, especially when they are enthusiastic and motivated. So thank you, Alexa, and good luck.

the dynamic anatomy so learn the anatomy in a context rather than looking at the the dead guy on the slab as a we would a cadaver look at this as a as a fluid model and I think that that's going to provide you a much greater useful model in the future. So I wish you luck. The thing that I would also encourage you to do is get really good at what you do first. So spend a lot of time learning, spend a lot of time practicing you're going to fail a lot it's important that you fail but you fail safely you never hurt anyone but it's important that you fail and then i would say you need to find a mentor someone that can lead you because there are elements of of understanding that can't be written down they can't be expressed easily this is what we call tacit knowledge and this is what you acquire from a mentor, from experience. And so this is where your focus needs to be for the next three to five years. And by then, you should start to get better at determining from a probability standpoint what would be the best course of action. This is how you're going to get good as a physical therapist. So hopefully that provides you a little element of guidance in this regard. And by all means, keep asking questions, always ask questions. and try to answer them yourselves and then seek out the answers from other people and other resources. But keep the questions coming towards me. I'm happy to help you. I love working with students, especially when they are enthusiastic and motivated. So thank you, Alexa, and good luck.

I've got some really, really good friends in baseball and I will trust in them to help me understand it better and we will move forward in that regard. I apologize for the bias and the strong opinion, but I believe it needs to be said so we can progress. Regarding Nick's question: instead of the typical I's, T's, and Y's, are there other ways to challenge the rotator cuff for a baseball player? Of course there are. The rotator cuff does not behave in isolation; it is involved in any movement that utilizes the upper extremity, whether supportive or active. But you do raise an interesting point. I plan to create a video on the I's, T's, and Y's because I think they are prescribed one, too often, and two, incorrectly. It's applied as a blanket exercise when, in reality, if you prescribe it to the wrong person at the wrong time or in the wrong context, you're creating a problem. Let's return to the original question: should arm care be aimed at increasing the dorsal rostral space? Maybe, if that's the specific need of the individual. There are two extreme archetypes of pitchers, and some will benefit from increasing dorsal rostral space more than others who may already have it. So, under certain circumstances, the I's, T's, and Y's are a great exercise for a specific type of pitcher with a particular structure. For others, it is the worst possible thing you could do because it actually steals the expansion element they need to position the ball. When we talk about the cocking phase of throwing a baseball, if I lack dorsal rostral space, I have to create a compensatory strategy to cock the ball, which is generally not the best choice. Again, if I am already compressed in that area and I prescribe the wrong exercise, such as an I-T-Y for that individual, I have just magnified the compensatory strategy they will use to throw. Now, perhaps it appears that you have enhanced performance in some cases. For instance, some people actually increase their velocity when using a compensatory strategy. If that is your goal—to amplify that capability—then you are successful. But we must understand the secondary consequences. If you risk other body parts, are you promoting the possibility that the pitcher will now have to pitch through lower back pain, elbow pain, or shoulder problems? There are any number of such factors, and that is what makes this so complex. While we want to be right and it is easy to preach opinions about arm care and physical structure, when we look at the individual, we have to make decisions about what we are trying to achieve and what outcome we desire, with the understanding of the secondary consequences. That is something I cannot predict, nor can you; it is something we have to assess based on the individual's experience, bringing us back to the n-of-one, within-subjects design model. This is how we must proceed, but we must do so with great care and concern, avoiding large leaps of probability. We must work within a framework that allows us to provide ultimate protection while we pursue performance. Again, this is very difficult; there is not one single right answer, but many possible right answers. However, I love that you asked the question because it raises significant concerns about how we often prescribe exercises blindly and simply cannot do that. We have to start viewing people as individuals.

Are you going to promote the possibility that we now have a picture that has to pitch through lower back pain or elbow pain or shoulder problem, etc.? So there's any number of these things, and that's what makes this so complex because as right as we want to seem and as easy as this is for me to sit here and preach my opinions about arm care and physical structure. When we look at the individual, we have to make decisions about what we're trying to chase, what we're trying to achieve, and then what is the outcome that we desire. With the underlying understanding of the secondary consequences, and that's something that I can't predict, something that you can't predict. It's something that we have to look at as the individual's own experience, and now we're back to n equals one. We're back to the within-subjects design model, and this is how we have to move forward, but we have to move forward with great care and concern and not make these giant leaps of probability. We have to work within a framework that allows us to provide the ultimate level of protection while we chase this performance. And again, this is very difficult. There's not one right answer; there are many right answers that are possible here. But I love the fact that you asked that question, because it does bring up a lot of concerns in regards to how we prescribe exercises blindly in many cases, and we just can't do that. We have to start looking at people as individuals.

So I can allow this expansion to occur here at the sternum, which provides me the positioning to allow this internal rotation to occur. So I have to look at the two ends of the muscle as behaving differently. And so again, that's why limiting our thought processes to a shortening contraction versus a lengthening contraction. I could be lengthening it at one end of the muscle and concentrically orienting at the other end of the muscle simultaneously to allow these movements to occur. That's why we have to look at this as shifting volumes and pressures and then shape, because the shape of the muscle doesn't necessarily mean that I am contracting at both ends when I say it's concentrically contracting. I can have an eccentric orientation at one end and a concentric orientation at the other that allows movement to occur at one end and limits or creates motion that occurs at the other end. This is a very, very important thing to understand because this is how we perform. Nick, I hope that answers your question. We're going to talk a little bit more about these kinds of things in regards to baseball and movement as we move forward because we're getting a lot more questions in regards to performance.

So again, I would encourage you not to think of anything in isolation short of something that's very, very clinical that maybe needs to be done to allow us a window of opportunity to do something that's a little bit more global and integrated. So again, thank you for that question, Nick. That was pretty awesome.

So we're not blindly applying this under every circumstance. Justin continues, what is the specific shape change of the pelvis you were attempting to create with my lateral slide drag video? So we kind of covered this a little bit earlier, but let me just reiterate. As we're creating the thoracic compressive element, those mechanics will create a downward pressure down towards the pelvis which will actually enhance our ability to reshape the pelvis as well. Then you superimpose the stepping element and we're using muscle activity and under this circumstance when you're looking at the lateral sled drag what I'm trying to do is create a posterior expansion of the pelvis on the left maintain the anterior compression and then we're trying to flip flop that entire circumstance on the right side so we're actually expanding the left posterior we're compressing the right posterior and reshaping the pelvis under those circumstances simply by driving the stepping strategy. So hopefully that answers your shape change question. Justin continues. In the video that you posted with the padawan talking about cutting and pitching mechanics, I believe you allude to a yielding contrast on the posterior thorax on the side of the turn. I've always been under the impression that in order to turn, you need to bias air into the anterior thorax and bring the pump handle up. Can you clarify the shape change of the thorax associated with the rotation where we need to yield and overcome in order to have the most efficient strategy for something like change of direction and fishing baseball? I can actually give you a great representation. I spent all day yesterday in my crafty lab, if you will. So I created a little bit of a thorax here. So the stick's gonna be the spine. I got a little bit of a sternum here. We're gonna call this a lower sternal rib. So this is gonna be one of the ribs, like three through six maybe. And then I got a first rib up here. And so what I'm gonna do is I'm just gonna reorient this so you can see it. So we're gonna look up inside the thorax. And hopefully you'll be able to see this on camera. And I will influence the sternal position and now I will turn the spine. And so let's just say that I want to make a right turn. So right is going to be in this direction, okay? So I'm going to lift the pump handle up on the left so you can see that right away. And I'm going to turn the spine this way. And so you'll see the shape change right there. Okay, let me get a little bit closer to the camera. Okay, so what I have is an anterior expansion on the left and a posterior expansion on the right, and that creates a right turn. And so if I was gonna flip flop and go the other way, you can see that I expand on the left posteriorly and expand on the right anteriorly and that's a left turn. And so these are the mechanics that we need to try to influence. So as I step back on the right or as I move into a cut on the right, I'm gonna be in that orientation there. As I push myself out, I'm gonna reorient and I change direction. So this is how we create the shape change in the thorax. So hopefully that gives you a little bit of a visual representation of the mechanics that we're actually talking about. Cause I do think there's a misunderstanding as to how we turn. Again, if we don't have these expansion and compression capabilities, we have limited turns. Again, these are the choices that you're going to make under certain exercise circumstances or activity circumstances to reinforce or to limit those. Again, if I have somebody that isn't much more linear or straight ahead athlete, I'm gonna try to eliminate a lot of those turning mechanics, but for baseball players, for dynamic athletes on the field, then I wanna start to reinforce these kind of mechanics. And so hopefully Justin, that clarifies a little bit of your turning question.

And so if I was going to flip flop and go the other way, you can see that I expand on the left posteriorly and expand on the right anteriorly, and that's a left turn. And so these are the mechanics that we need to try to influence. So as I step back on the right or as I move into a cut on the right, I'm going to be in that orientation there. As I push myself out, I'm going to reorient and I change direction. So this is how we create the shape change in the thorax. So hopefully that gives you a little bit of a visual representation of the mechanics that we're actually talking about. Because I do think there's a misunderstanding as to how we turn. Again, if we don't have these expansion and compression capabilities, we have limited turns. Again, these are the choices that you're going to make under certain exercise circumstances or activity circumstances to reinforce or to limit those. Again, if I have somebody that isn't much more linear or straight ahead athlete, I'm going to try to eliminate a lot of those turning mechanics, but for baseball players, for dynamic athletes on the field, then I want to start to reinforce these kinds of mechanics. And so hopefully Justin, that clarifies a little bit of your turning question.

I suggest you try to own this. You may want to go with the Kindle unless you're really, really strong, because this is like 1500 pages or something like that. But great, great embryology. The other embryology resource I like is Larson's. If you want to take a look at that. So understand where you came from. I'm a big fan of that. So when you understand the structure of the internal organs, it lends itself to how a lot of those organs are oriented and behave. And then it's just a matter of understanding how it moves when we move. So now we're back to physics. We're now we're back to fluid movement, ingredients and such. So you got to put the structure together. You got to put the physics together. And then you just basically start to pay attention to how we move and what these internal organs could be doing under certain circumstances. So much like a wave crashing into a rock, those organs are constantly moving inside of you. They produce forces that we have to manage. And a lot of times, especially when we see our young athletes performing agility activities and we see their lack of control in certain elements of cutting and deceleration, we can actually identify or picture what these internal forces are doing to produce the external strategies. And then that allows us to make some decisions in regards to training. And then it's just a matter of determining, do we get the outcome that we desired? Were we correct in our assumptions? And then we're working again based on probabilities, which is how we do everything when we're dealing with humans. So hopefully, Brian, that gives you a place to start. So to reiterate, embryology and physics and observation. So go with those three elements.

And this is the position that allows the lower cervical spine. So we're talking about C3 and below to turn. So if I have something that cannot turn the lower cervical spine in one direction, chances are you've got a compressed dorsal rostral area on the same side. You will see a deficit in overhead reach, the inability to flex the shoulder and turn the lower cervical spine in an ipsy lateral, same side direction. And so we have this direct relationship that is involved with dorsal rostral and lower cervical. When we talk about the upper cervical spine, it should turn in opposition to the lower cervical spine. So again, if I have an upper cervical deficit, I need to make sure that I have a lower cervical spine that can turn in the opposite direction. So again, I can use my overhead reach, my shoulder flexion measurement to help me determine whether I have lower cervical spine rotation or whether I have an upper cervical spine deficit as well. So keep that in mind. So think dorsal rostral first, I have to have the capabilities there. That's going to free up the lower cervical spine for rotation. So as I inhale the dorsal rostrum, I must have an inhaled position of the lower cervical spine, which is lower cervical spine flexion, and then upper cervical spine extension. And that's going to allow me to restore all of those movement capabilities. So hopefully that leads you in the right direction, Misha.