Strengthening an Imbalanced Knee



When I’m working with people, in pretty much any physical/movement context, a complaint that comes up again and again is knee pain, or even just “knee niggles”. 

While there are many things that can be causing issues with our knee, again and again I find that it is an imbalance between the muscles on the outside of the leg and the muscles of the inside of the leg that is causing this problem.

For a long time this problem will just cause the odd little tweak and twinge, perhaps a popping or clicking; but if this unbalance is left to continue more significant issues can occur such as a subluxation or dislocation.

What is this Cause of this Imbalance?

To understand this we need to take a quick look at the anatomy of the knee, and specifically two of the muscles that make up the quadriceps muscle group.

On the diagram here we will see that the Vastus Lateralis is the muscle that comprises the outside edge of the thigh, and the Vastus Medialis serves a similar role on the inside.  The Vastus Lateralis, is naturally bigger than the Vastus Medialis, but both muscles should be proportionally well developed. 

An imbalance begins to occur when the Vastus Lateralis, the muscle on the outside, becomes so dominant and strong that the inner muscle, the Vastus Medialis, begins to under-recruit.  This leads to a feedback loop that continues to reinforce the unbalance, the big strong muscle taking over and the under-recruited muscle becoming ignored and atrophying. The result of which is the Vastus Lateralis begins to pull the kneecap to the outside, because the Vastus Medialis doesn’t have the strength to stabilise it.

There can be many causes of this imbalance, but in my experience it tends to be extremely common amongst those who spend a lot of time sitting down.

Do *I* have an Imbalance?

The easiest way to check this yourself is to extend your leg or sitting on the floor and compare the muscle tone on the outside edge and inner edge of the thigh where it is meeting the knee.  If the inner edge at this point (The area known as the Vastus Medialis Obliquus – or VMO) feels “empty”, especially in comparison to a strong “full” muscle on the outside you may be encountering this imbalance in your body.

At this point you should check with a doctor, physiotherapist or other body working professional who can confirm the diagnosis.

Resolving the Imbalance

At least half the battle in resolving this problem, is being aware that it exists.  When you become aware of it you can start to bring attention to this area of your body when you perform any exercise, or even any activity.

For example.  Try standing up from a chair with weight to the outside edges of your feet, your knees will splay wide, inscribing an ellipse as you stand up. Do this a couple of times and you will feel it is the large lateral muscles on the outside of your thighs that are propelling you here, and at the is no connection with the muscles on the inside of the legs.

Next, try standing up from the same chair, but this time ensure that your weight presses down on the pad behind your big toe as you stand up. This time your knees don't inscribe an arc, instead you stand up more directly. Repeat this a couple of times, and you can learn to feel the connection of the muscles on the inside of the thighs engaging as you stand up.

Just by bringing intention to this area in everyday life you can begin to teach the muscles to recruit and activate.

However, if the imbalance has already begun to grow, it is definitely going to help to carry out some exercises that will recruit and strengthen the Vastus Medialis. 

In this workout below I’m including four such exercises which can be carried out anywhere and without the need of weights or other gym equipment.  

Remember this problem will only get worse if not attneded too - but it can be resolved with a little focus and dilegent attention.

Vastus Medialis/VMO Stability Workout

Exercise 1:  Knee Extension

To carry out this first exercise rollup a towel and place it under one or both of your legs.

Then ensuring you are sitting on your sitting bones, with your legs stretched out in front of you slowly extend the right leg until it is straight.  When you do this concentrate on engaging the inner thigh area.  Don’t rush the exercise, do it slowly and with control.

Repeat 10 times on each leg.


The exercise can work well set up against the wall, this can help ensure that you don’t slump down in the back.

In the gym a similar exercise can be carried out with the leg extension machine on a low weight. Set the machine so that you are only moving the last 10 or 15°, and focus on engaging the muscles in that VMO area above the knee and to the inside of the thigh.



Step Up

You can perform this exercise on any step, even a staircase at home.

To be honest a staircase would probably have been better than the gym I was filming in here, but I made use of a running machine as a makeshift step.

The important thing is that we are focusing on the engagement of the standing leg with which we are stepping up.  Be conscious of your movement, and ensure that you are pushing down with the pad behind the big toe, drawing the kneecap up, and look to feel the engagement of the muscles on the inside of the thigh.

Again work slowly, and perform 10 repetitions on each side.


Tree Pose

This classic yoga pose is great for becoming conscious of the way your muscles are working on a single leg balance.  The placement of the 2nd foot to the inside of the standing leg is a great help in bringing our attention to engaging the Vastus Medialis.  When you do this exercise keep your focus on the standing leg, try to fill the engagement of the muscles on the inner thigh by drawing your kneecap up and keeping your weight towards the pad on the big toe, not pushing out to the little toe edge of the foot.

As you can see on the video, depending upon level practice with this technique you can start with the 2nd foot still on the ground but turned to rest against the ankle of the standing leg, or draw that leg up so that it presses against the inside of the calf or thigh. 

When doing this however ensure that you do not push against the inside of the knee directly! 

Hold this pose for 30 seconds on each leg.


When you get more comfortable with this pose there are many variations that you can add in.  Such as bringing the hands from the hips to prayer position or above the head, or even adding a squat element by bending the standing leg.  (As seen in the photo here.)


Standing Side Stretch with Twist

While you see variations on this sort of side stretch used in many athletic warmup routines, I came across this variation with the torso twist to the inside from a Shadow Yoga teacher.

When I did the exercise I felt my Vastus Medialis fire, and I immediately thought that I could use this when working with people on this issue.

As you will see in the video we start with a side lunge but then turn the torso towards the extended leg and foot.  I’ve added taking the hand to the inside of the knee/lower thigh for this routine.  The idea of this is to push a little against the muscle we are trying to work to help bring our attention, and our bodies engagement, to this area.

Perform 6 to 8 repetitions of this exercise on each side.  This is an exercise that can be added to any mobilisation or warmup to keep reminding her body to engage this muscle group.



Supported Pistol Squat

The tree pose this is another single leg balance, but now we are adding a squatting motion to work and build the Vastus Medialis muscle.

The full version of the Pistol Squat is a challenging exercise, but in this version take hold of something with your hand that you can use to support you as you stand on one leg with the other leg stretched forward. 

In the home this could be a door frame, or a stable table or chair.  (Do make sure it’s not going to move however!)

To begin, as you stand supported on a single leg, bring your attention and focus to the muscles that you are trying to engage and ensure your weight is to the inside not outside of the foot.

When you are ready, using the support for balance, lower the standing leg - squatting down as deeply as you are comfortable with for this exercise.

It’s completely fine if that only a few inches the first time you do this, you will still get a benefit.

As time goes on you will find you can squat down further, looking maybe to get to a 90° knee bend.  Who knows, maybe one day you will be able to let go of the support and to the exercise freestanding?  It’s difficult, but achievable, goal for many of us!  :-)

David EllardComment