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Overactive and Underactive Muscles Part 1: FEET TURN OUT – KNEES MOVE IN

According to listener feedback and requests, a discussion on over- and underactive muscles was the most popular request. This is part 1 of 3 episodes where this topic will be discussed. This episode will cover two common movement compensations in the overhead squat assessment:

  • Feet turn out
  • Knees move in

A review of short muscles that lead to this compensation and lengthened muscles that allow the compensations to occur. These episodes will be anatomy heavy and may help the listener better understand functional anatomy. Functional anatomy helps listeners better understand how muscles can contribute to movement compensation and dysfunction.

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You’re listening to The NASM-CPT Podcast with Rick Richey, the official podcast of the National Academy of Sports Medicine.

Welcome to The NASM-CPT Podcast, my name is Rick Richey and I want to thank every single one of you who have put out information towards us and said “Hey, there are topics that I wanna hear about,” because what we’re going to talk about today and we’re going to extend this over several episodes, is the most common topic that we got people asking questions about. And people want to know about overactive and underactive muscles.

And I’m assuming this is specifically about the overhead squat assessment and what we’re looking at. And I would also assume that this is about test taking. So for those people who want a little bit more understanding going into the training protocols, getting into personal training and understanding assessment. But also for people who are weak trying to get a little better at the exam, then maybe these will be helpful for you in discussing the overactive and underactive muscles. Because this is such a… I’m not gonna say a deep topic, its an expansive topic.

We have several different compensations we’re going to be looking at, so what I’m going to do is I’ll expand this over several episodes and in this episode we’re going to address two things: we’re going to address feet turn out in the overhead squat assessment and what muscles are overactive or underactive or shortened and lengthened.

And then we’re going to talk about knees move in. So these are the two compensations we’re going to address. We’ll talk about what muscles might be short, tight, overactive; what muscles might be lengthened and underactive. And we may highlight a little bit of what you might wanna do once you find those muscles, and identify whether they are over or underactive; whether they are short muscles or tight muscles. Let’s get right into it.

The first one we’re going to look at will be feet turning out. So if you have somebody doing an overhead squat assessment you’re lining them up, in what we would look at as ideal and optimal alignment, so initially you’re gonna set ’em up feet completely straight ahead; second and third toes pointing straight ahead, knees in line with second and third toes, hips in a neutral position, so have an anterior and posterior tilt, and find their current middle and then take the arms over the head, with the chin in a neutral position. You’re going to have them descend down into a squat, watch them move and as you see them move, you might notice that their feet turn out.

Now what is technically is happening here is most likely the weight is being pushed onto the ball of the foot, the heels are rising and the heels are actually shifting in, but we refer to this as a feet out position. So heels in and feet out are quite technically the same thing, but there’s some mechanics as to what is actually happening, so people don’t rock back on their heels, lift the balls of their feet and turn their feet out. They move onto the balls of their feet, their heels lift up and it shifts that way. So if we look at this, we have to say something is not allowing the range of motion for the descent to take place into the squat and for the feet to stay completely straight ahead. So what we’ll look at are the muscles that are initially overactive.

Now if we look at an overhead squat assessment, this movement itself is a sagittal plane movement. And what we are seeing is a deviation in potentially both the frontal plane and the transverse plane. Now the frontal plane might be the collapse of the medial longitudinal arch of the foot and, then the transverse plane compensation would be the feet abducting or turning out, so what the reason that is ‘cos you don’t have enough sagittal plane range of motion and we start to steal from other planes.

Now if we look at this, let’s start to identify why. The first thing we are going to look at is I don’t have enough dorsiflexion. Dorsiflexion is when, let’s look at shin on foot dorsiflexion. That’s where we’re paying attention to, so as you’re standing up straight there’s about a 90 degree angle from the top of the foot to the anterior front part of the shin. When you go down into the squat, the shin moves forward towards the foot. And, that’s going to create dorsiflexion. That is dorsiflexion. It’s Tibia on foot dorsiflexion.

Now, I’m looking specifically at the inability to dorsiflex while going into the squat. Some people do this by a conscious choice by not letting their knees go past their toes; it’s fine if your knees go past your toes. What you really don’t want to do, is have your heels lift up off the ground. You want to share the weight in the front of the foot, or the ball of the foot and the heel of the foot so that should be equally distributed. So if you’re shifting weight towards the ball of the foot, then you need to kind of balance out that position, but if your knees go past your toes and you still have weight evenly distributed along the foot, it’s actually absolutely fine.

So, if I don’t get that dorsiflexion, that range of motion, there are several muscles that are going to be considered overactive, so they’re short and they’re not allowing for extensibility.

The first muscle we are going to look at will be the Soleus. The Soleus is one of the calf muscles, it is a deeper calf muscle and as you, and it’s a plantar flexor. Concentrically it does plantar flexion, and eccentrically it decelerates dorsiflexion. So concentrically it plantar flexes or, allows us to point our foot. If we go into a dorsiflexion position, it will decelerate that or try to limit that, or slow it down. In this particular incidence it is not allowing us, it’s one of the muscles that may not have been allowing us to go into dorsiflexion.

So it’s the only one in the group of these overactive muscles that don’t actually have a lateral moment arm to pull you into abduction, or to make the feet turn out. The reason it does what it does, is because it works only in the sagittal, primarily in the sagittal plane and it limits dorsiflexion, but if you don’t have dorsiflexion in the sagittal plan, that’s when the cheats come in. Then, if you’re limited then you start to flatten your foot. So that is a frontal plane cheat, you start to abduct your feet. That is a transverse plane cheat. But because I can’t get dorsiflexion in the sagittal plane, you’ll start cheating and stealing from other planes of motion, do the soleus is an example of that. Now the feet turn out, now there are some muscles that force the feet to turn out. The soleus isn’t one of them, it doesn’t have a rotational component, it’s just a sagittal plane mover. But when you don’t have that range of motion you’ll start to steal from other planes.

Now, the lateral gastrocnemius is going to be our second muscle that we’ll discuss here and it is a plantar flexor, so it will also limit dorsiflexion. If I don’t have enough dorsiflexion, then that muscle will be a big component of it. But the lateral gastrocnemius has a lateral rotation at the tibia so it can make the knee actually create external rotation at the tibia and that’s what will make the feet turn out, so it is the rotation at the tibia that can cause the feet turn out. It also will have a pull at the calcaneus for eversion as well. So we look at the lateral gastrocnemius, there are several components that is going to be working through here; it’s got limited sagittal plane range of motion, if it’s tight and it can create cheats in other planes. But because it’s got that momentum on the lateral component, it will create a rotation; external rotation, and so that’s what can cause the feet to turn out.

We also have the biceps femoris, so this will be the last muscle that we’ll talk about and, this is like a, this is not a corrective exercise course, this is the CPT Podcast, and we’re gonna address this right now, just as, what we need to know in our current iteration of our content for feet turn out.

So it will be three muscles; the soleus was the first one we talked about, lateral gastrocnemius is the second, and the third will be the biceps femoris. But, specifically, the short head of the biceps femoris. The short head of the biceps femoris will begin or have it’s proximal insertion on the femur and it will cross over the lateral part of the knee, I mean, you can feel where your biceps femoris is. If you just go to outside of your thigh, close to your knee and you feel the hamstring, just those tendons really close to the knee, and then if your knee is bent like you’re sitting at a chair, all you have to do is laterally or externally rotate your knee and you’ll feel that muscle pop into your fingers like, like as you’re pressing into it, it’ll push out against your fingers.

So that muscle is concentrically contracting as you go into external tibial rotation. Well external tibial rotation is feet turn out. So it’s a component of that, now when the short biceps femoris, short head of the biceps femoris gets short, tight, overactive it’s going to create that tibial rotation and cause the foot to turn out. We see this a lot of times, I see this if I just have someone do a balance exercise; stand on one foot, lift up the other leg and when they lift up the other leg, their knee might be pointing straight ahead, but their foot is rotated out to the side. That’s just a secondary assessment that I utilize personally when I’m working with my clients, I want to see when they lift their leg up does their foot automatically turn out to the side. And that gives me an idea of lateral gastrocnemius, biceps femoris. Those muscles are having, are short causing this joint action to take place, and it’s one that we don’t necessarily want, and it can lead to other compensations.

But here’s a problem, when that happens, yes, these muscles are overactive and they are pulling us out of an ideal alignment but there are other muscles that are letting it happen. There are other muscles not doing their job to help maintain a neutral position and they’re losing to the overactive muscles which is why we’ll refer to them often time, as underactive. They’re not doing their job in order to maintain neutral alignment. So our first muscle that we will look at on the underactive list is going to be the medial gastrocnemius. The medial gastrocnemius will have that medial tibial rotation that you would see at the tibia, right, so it’s there obviously. But, the medial rotation at the tibia will realign the foot, so the medial gastrocnemius is not doing its job to balance out what the lateral gastrocnemius might be doing.

Same thing with the medial hamstrings, so my semimembranosus, my semitendinosus, these are not as strong usually as the biceps femoris and that’s why when you see people doing, let’s say seated hamstring curls or prone hamstring curls and their feet are turned away from each other, like they just had an argument and they are just not talking to each other right now. When the feet are turned out like that, that’s the biceps femoris really taking over and a lot of times, people will continue to add weight and do it wrong rather than keep the feet in a neutral position because they have to take the weight down because the weaker muscles; semimembranosus, semitendinosus, the medial hamstring complex, they are weaker and it’s kind of sometimes an ego thing where we don’t want to lighten the weight in order to maintain the movement that would be ideally precipitated.

There are other muscles that will be underactive, these are primary tibial internal rotators that, that play a very important component of this. Muscles like the gracilis, the sartorius, sartorius. So we’ve got the gracilis, sartorius and popliteus. The gracilis is an adductor, it is the only adductor that crosses over the knee and it creates medial tibial rotation. Sartorius is the longest muscle in the body and it will create medial tibial rotation and the popliteus will create medial tibial rotation.

So, here’s what’s gonna happen, we’re gonna to look at the overactive muscles, the muscles that are short, pulling into compensation with feet turn out in the over head squat assessment. We got soleus, lateral gastrocnemius and biceps femoris short head. What do we do with those muscles? Well foam rolling would be high on the list here, so you might foam roll those muscles.

What else would you do? You static stretch those muscles. So static stretch is a form of corrective exercise, and clearly these guys need to be corrected. So, let’s down regulate the facilitation of these muscles through static stretching; through foam rolling first then static stretching and then the underactive muscles, what do we do? We activate, we create facilitation towards them, so we give exercises that are going to preferentially activate the medial gastrocnemius, medial hamstring complex, and other internal rotators like the gracilis, sartorius and popliteus.

All right, let’s move from feet turn out to knees move in. This will be the last compensation that we will talk about on this particular episode. But, let’s do a highlight reel, right now, what we’re going to look at: knees move in, the overactive muscles, are the muscles that are creating a shortened position and pulling into the compensation.

Overactive muscles, with the knees move in, in an overhead squat are the adductor complex, so causing the knees to move towards the midline of the body. Biceps, femoris short head; so there’s a throw back to our previous one, tensor fasciae latae (TFL) and the vastus lateralis and we’ll discuss the VL, the vastus lateralis a little bit more. So, overactive muscles, adductors, biceps femoris short head, TFL and vastus lateralis. What are the underactive muscles when the knees move in in an overhead squat position? The glute medias, the glute maximus, the vastus medialis oblique or the VMO.

So the overactive muscles, let’s talk through these things real quick. If I go in an overhead squat; my client does, and I see their knees move in towards the midline of the body, so there’s medial knee displacement, there’s adduction, movement going towards the midline of the body, my first thought would be and should be probably adductors that might be pulling these towards the midline of my body. They are shorter, tighter, maybe more overactive and then the biceps femoris and the TFL.

Now these two are very interesting, so stick with me for a second. Biceps femoris had the, the tibia external rotation or the feet turn out, but we can also see that the knees move in, now if the knees move in relative to the knee, it’s still tibial external rotation, relative to the foot, you might see that the feet adduct. But, when you do this, you’ll see that there is what we will refer to as a bow-string effect, this will happen for the biceps femoris and the TFL, that the tissue on the outside of the muscle, usually in a closed chain when this happens, the outside, sorry the muscles on the outside of the joint at the knee, when they start to get tight in a closed chain will actually displace medially, will force the knee to move in towards the midline of the body, instead of being tight on the outside and pulling it into adduction, it’s tight on the outside like a bow-string and if the joint at your knee, is the bend in the bow it will squeeze on the lateral side, tighten on the lateral side of the leg and create medial knee displacement, cause the knee valgus or the knees to knock. The TFL will do that too, TFL has that component as well, but it’s also an internal rotator of the hip.

So, a lot of times the knees move in, it’s because of adduction and internal rotation at the hip. So when my hip adducts, when my hip internally rotates, my knee is just an extension of my hip at the femur, right so my femur moves in and my knee will then follow that. We are going to see this component take place where there is adduction and internal rotation with the TFL in a closed chain and then the vastus lateralis. Vastus lateralis is the big quadriceps muscle on the lateral side of the thigh, so the big quad on the lateral side of the thigh. It is actually not creating the valgus but it is affected adversely by the valgus. What happens? There tends to be a tighter muscle tissue on the lateral side when the valgus or medial knee displacement starts to happen and it can create an adverse effect on the patellar, or the knee cap and start to lead to lateral tracking of the patellar and so as it pulls laterally on the patellar it can take it out of its tracking and there is a little sulcus between when you get towards the most distal part of your femur; it’s the little dip in between the notches of the femur, and the patellar should ride right in-between those notches and if we get lateral pull on the patellar then it starts to throw that tracking off.

Well what do we do about this? Well yes, we’ll foam roll the adductor; biceps, femoris, TFL and vastus lateralis. We can stretch those muscles, but that’s not enough we need to go to the underactive muscles, the muscles that that are allowing medial knee displacement, or the knees to move in, and they should be strong enough to at least maintain neutral position. So the two primary muscles that we’d be looking at are at the hip, it’s going to be the glute medias and the gluteus maximus.

The glute medias’ primary job is to adduct the hip, well when the knees move in, that means we are adducting the hips, it is a primary component of what would be going on here. The glute medias is the muscle that should be strengthened to minimize the medial knee displacement, and there is many many research studies out there that support the use of glute medias activation in order to minimize medial knee displacement, or knees moving in. The other muscle, primarily that would be a component that you would look at, that would be the glute maximus. The glute maximus is, it’s an extensor; your primary hip extensor, its an adductor, it’s an external rotator of the hip, all of those things.

Well, in an overhead squat assessment, you’ve got hip flexion, knee adduction and knee internal rotation when the knees move in. So when the glute max, actually does the opposite of all of those things in this particular disfunction. So the gluteus maximus will also be a very important component for activation when it comes to controlling the knee valgus taking place. And, the other muscle that we have here is going to be the VMO, and the VMO again it’s a byproduct of knee valgus and something that needs to be worked on. It won’t stop knee valgus from taking place, unlike the things like strengthening glute medias and glute maximus will minimize that. Knee valgus when we look for the vastus medialis here, it’s particularly because we want to realign the patellar and to get it lined back up so we are no longer having the medial, the lateral tracking issues where the patellar is being pulled laterally towards the vastus lateralis, the vastus medialis oblique is going to pull it back into it’s neutral position. Ideally that’s what we’re looking at.

So, we’ve got, knees move in, overactive muscles; adductor complex, biceps femoris, short head TFL, vastus lateralis, the underactive muscles; glute medias, glute maximus, and the VMO.

I hope that this review is very helpful and if it is, listen to it again, study it again, share it with your friends and people who you know might be going through trying to figure out what this process looks like. If I’ve muddied the water for you, reach out to me, let me know and see if I can create some clarity, provide some clarification for what we are going to be talking about. But, with that being said, thank you so much for listening to the podcast, for promoting it, for sharing it, for all that you do to help us maintain and continue to grow this podcast. If you could share it, like it, subscribe it, all of that stuff, it’d be greatly appreciated and we will continue to accept feedback and topic ideas from you.

So you can reach out to me rick.richey@nasm.org or hit me up on Instagram at @dr.rickrichey and we can talk about, shoot me the topics you want to hear, what’s on your mind and provide some feedback on the podcast. Anyway this is the NASM-CPT podcast, thank you for listening.

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National Academy of Sports Medicine

National Academy of Sports Medicine

Since 1987 the National Academy of Sports Medicine (NASM) has been the global leader in delivering evidence-based certifications and advanced specializations to health and fitness professionals. Our products and services are scientifically and clinically proven. They are revered and utilized by leading brands and programs around the world and have launched thousands of successful careers.


  1. Erin B
    September 27, 2019 at 6:53 am — Reply

    THANK YOU for creating episodes on muscle imbalances and compensations! Please keep it coming! I feel this is the hardest material to grasp, remember and apply. More, more, more!

  2. October 3, 2019 at 12:53 am — Reply

    I read your blog! In this episode, you have explained it so well about the muscles. Keep up the good work!

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