Using VMO exercises but seeing no relief from knee pain? Let’s discuss why these don’t work (despite what you’ve been told) and what WILL ease the pain.
Quads & The VMO Scapegoat
Your quadriceps muscles are key to so many movements and activities that you do. The group is made up of four muscles (a “quad”) – rectus femoris, vastus lateralis, vastus intermedius, and vastus medialis obliquus (the VMO).
The VMO is the most medial of your quadriceps muscles, and one often blamed for knee issues like patellar tracking disorder and patellofemoral pain syndrome (PFPS) – a broad term for pain around the front of your knee.
This muscle often gets the blame simply because of its positioning closest toward the midline. It is thought this positioning helps to keep your kneecap in proper alignment . However, as we’ll learn, strengthening all of the muscles that affect the knees is key to their health, which include but aren’t limited to the quads (more on that later).
The vastus medialis, intermedius and lateralis originate on the femur, while the rectus femoris originates on the ilium on your pelvis.
All 4 then run down to your knee and insert into the patella via the patellar tendon. At this point, the muscles all join together, becoming a single tendon that surrounds your patella, or kneecap. This tendon then continues down to connect to the tibia of your lower leg .
Thus, the vastii muscles are single joint that perform knee extension.
The rectus femoris is a two-joint muscle, which works to extend your knee and flex your hip.
Your quadriceps are crucial to everyday life tasks like walking, going up stairs, and even just standing upright .
The functioning of these muscles is also crucial to all sorts of sport functions. Running around the bases or track, jumping up to shoot the basketball or do a jump squat, kicking a ball or a boxing bag… all of these activities rely on the functioning of your quads. And all of these activities can take a hit if you’re suffering from knee pain.
The 3 Reasons VMO Exercises Won’t Cure Knee Pain
Although the VMO is the traditional scapegoat for knee pain, the latest evidence is proving that focusing on this muscle and this muscle alone won’t cure your knee pain. Let’s take a look at the 3 reasons why.
1) All of the Quads are Involved
For people with PFPS, weakness in all portions of the quads is present, not just the VMO. And yet, strengthening only the VMO is the classic go-to recommendation.
For example, one study looked at the quad muscles of 35 people with patellofemoral pain around the front of their knee. The study found that ALL of the quads were atrophied on the painful side, and that the VMO muscles didn’t stand out as selectively atrophied .
Because all of the quads are weakened, it makes sense that all of the quads require strengthening – not just the VMO. And focusing all your energy on strengthening only the VMO is addressing only a small fraction of the problem.
2) Effectively Targeting the VMO is Tricky
Another reason that focusing on the VMO alone won’t heal your knee pain is that it’s just plain tricky to effectively target this muscle.
It’s hard to isolate this medial quad, and trying to do so can prove very difficult to someone training alone.
In order to target it, it usually requires adding hip adduction to your knee extension – i.e., straightening the knees while squeezing them together.
However, research is suggesting that these motions only provide slightly more VMO activation . And what’s more, the motion can be problematic and might just be training a dysfunctional and possibly unsafe movement pattern.
Hip adduction promotes valgus knees or knock-knees, which can be a precursor to a lot of knee problems, plus a lot of problems up and down the kinetic chain.
Too many attempts at VMO activation, especially when not done correctly, might just be working to reinforce a poor alignment – and it doesn’t even give you significantly more VMO activation for your trouble!
3) There’s No Evidence for VMO Isolation
The simple truth of it is that VMO isolation hasn’t shown positive outcomes. To stick with a method just because it is the one that has been traditionally used, despite a lack of evidence, just doesn’t make any sense.
That’s why we continually look at the research here at Precision Movement, to help us create innovative solutions for your movement problems.
VMO isolation hasn’t shown to help reduce knee pain, so we’re not going to waste your time on VMO exercises. Instead, let’s focus on strategies that HAVE been proven to help.
3 Things To Do Instead for Pain-Free Knees
Now that we’ve learned why the VMO exercises shouldn’t really be considered the gold standard of knee pain, let’s talk about what you should focus on instead.
There are a couple of simple strategies you can use to help improve the health of your knees – and your entire lower body.
These strategies don’t just focus on a single area, like the VMO. Instead, they consider the entire kinetic chain of the lower body.
This is important, because knee pain doesn’t just stem from the VMO. For example, research has shown that changes to hip kinematics can be a root cause of PFPS .
So, considering a more holistic approach will earn you much better results – not only when it comes to knee pain, but for preventing a ton of other issues, too.
1) Squat Deeper
One effective strategy is a simple one – simply squat deeper. Doing so can be an easy way to activate your VMO in a biomechanically sound position.
One study found that deeper squats (squats with a 50 or 80 degrees of knee flexion versus 20 degrees) created much stronger activation of the VMO .
Plus, squats are great at strengthening your hips and your glutes – 2 areas that can be key to knee pain.
For example, another study found that hip and knee strengthening combined (as in a squat) was better at reducing knee pain that just knee strengthening alone .
And yet another study showed that people with PFPS had increased pain with long periods of sitting – probably because your glutes shut off and stop functioning effectively after a lot of sitting, placing excess stress elsewhere, like on your knees.
So, not only can deep squats help you activate your VMO easily without knee adduction during extension, squats are a great way to improve our overall lower body mobility and strength while activating the glutes. What’s not to love?
Just be sure you’re maintaining good form and avoiding valgus knees as you work deeper squats.
2) Improve Your Ankle Dorsiflexion
Another wise area to focus on is ankle dorsiflexion – or the motion required to bring your toes closer to your ankles.
Research has shown that decreased dorsiflexion alters movement and activation patterns in a way that is very similar to patterns people with PFPS display, including increased knee valgus . Limited dorsiflexion not only affects the ankle itself, but the knee and hip as well .
Here’s a unique drill to improve BOTH the depth of your squat and your ankle dorsiflexion:
Do this drill as part of your warmup for 6-10 reps per side or at least 3 days per week (daily is best for the first week or two) and you’ll notice a much deeper squat and greater ankle dorsiflexion.
3) Get Your Feet Working Properly
For this last step, we’ll continue on down the lower leg to the feet. The root cause of knee pain for most folks stems from their hips or their ankles and feet – not their knees.
This is because the knee is a more simple joint where less can actually go wrong, whereas the hips and ankles/feet are way more complex with more muscles and have a much greater potential for dysfunction.
While people might try to improve hip strength and mobility, very few devote any effort at all to their feet.
My article on pes planus, or flat feet, gives a lot of advice on improving the strength and help of your feet. And whether or not your feet or flat, they could definitely use some attention and training.
Try to through in a few exercises focused on strengthening and improving muscular control and balance in the feet. Having strong and healthy feet and ankles provides a good base for proper functioning of your knees (and everything else).
So if you’ve been working VMO exercises and have seen no change in your knee pain or PFPS symptoms, try to broaden your approach and stop trying to isolate a portion of your quads and instead, work deep squats, ankle dorsiflexion, and build strong, functional feet.
Your knee pain will improve, as will your entire lower limb.