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It doesn’t matter if you’re a weightlifter, powerlifter, CrossFit® athlete, or you just like to squat heavy. If you like to squat heavy, there’s a pretty good chance that at some point, your knees have started to cave inward on the ascent.
It’s common, but it can have disastrous results, sometimes causing snapped tendons and even complete knee replacements. But usually it’s not the kind of problem that causes an automatic, acute injury. Instead, it creates small imbalances at the knee every time it tracks incorrectly, wearing away knee cartilage and eventually causing pain and immobility.
“Ideally, knees should track up and down the exact same way, just like a hinge opening and shutting,” says Dr. Aaron Horschig, a sports and orthopedic physical therapist, USAW Olympic weightlifter, and founder of Squat University. “Open it cleanly, the hinge opens nice and smoothly. As you as you get a bit of knee waiver, it’s like trying to open the door but simultaneously pulling up as you’re pulling out. You can only do that so many times before the hinge starts to wear out.”
So what are the causes, and what can we do about it?
Why Do My Knees Cave In When I Squat?
The knee is basically a hinge joint that’s stuck between two other joints that control it: the hip joint and the ankle joint. While we’re most mechanically efficient when the knees track over the feet, poor hip or ankle mobility can cause pretty significant restrictions on the way down to a squat.
“It reaches a point where there are two paths the body can take,” says Horschig. “Either the knee will collapse, or the chest is going to start collapsing because the knee has stopped moving forward, meaning the hips will try to push forward instead and the chest will collapse as compensation.”
When screening ankle mobility, he likes to administer the 5-inch wall test: can you touch the knee to the wall at a distance of five inches? If so, then ankle mobility probably isn’t your problem.
So mobility can be an issue, but usually it isn’t, particularly if you’ve been training for a while and don’t have old ankle injuries giving you problems.
If your knees cave in a little when you squat, does it happen on the descent of the squat? Does it happen when you’re using light weight? If not, it’s probably more of a coordination problem than a mobility problem.
“It’s not because they’re weak, necessarily, it’s because the timing of when the muscles activate is a little off,” says Horschig. “That can be either due to fatigue or neuromuscular control issues — you haven’t been primed to move that way every single time you squat, and when you get up to very heavy weights, the body can’t properly meet the demands of that increased weight.”
Basically, it’s harder for the body to squat heavy than it is to squat light. (Crazy, right?) That means the heavier the weight, the more neuromuscular control and coordination your body needs to maintain correct form and avoid knee valgus. For a lot of us, form starts to break down as the weight gets heavier, so how do you train the system to not do that?
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See this often when people squat. Knees caving in or better known as knee valgus increases the risk of knee pain, arthritis and ACL injuries. Solution: build ankle mobility, strengthen glutes and abductors (hips) forcing external rotation of muscles as seen on left. #correctiveexercise #acl #kneevalgus
How Do I Stop My Knees Caving In When I Squat?
If your knees cave a little bit but they don’t go further than your big toe, it’s not such a big deal. It’s not great, and it’s still a good idea to experiment with the following exercises, but you probably don’t have to drop weight.
But if as soon as you hit 80 percent of your 1-rep max, your knee goes further inward than your toes? You should probably stop squatting that heavy until you can correct the issue.
Yelling “knees out” in your head can be surprisingly effective, but Horschig says the key to fixing knee valgus is the pistol squat.
“A lot of the time athletes won’t show that bad coordination or movement in a regular squat, but when you give them a pistol squat it comes out,” says Horschig. “That’s because they have a poor ability to coordinate hip muscles and the glute medius, the muscle on the outside of the body that controls abduction. If that muscle isn’t working correctly, it allows the body to sort of compensate and allow the knee to cave in when it’s called upon to do a very powerful movement.”
So while hip abduction exercises are handy and squatting with bands around your knees is also great, you want to find a way to work in single leg movements too, as they’re more demanding. Horschig uses the following three, often before squats begin so as to prime the body to move well during the lift.
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The single leg pistol squat is a difficult movement for many people to perform. It requires a good amount of ankle/hip mobility, a ton of body coordination and excellence balance. Often athletes work tirelessly on perfecting this movement and still struggle with it. No matter how hard they try, they just can’t seem to perform a full pistol correctly😩 . I want to share with you today a simple 3-step beginner progression to building the perfect pistol. Perfecting these early steps will give you a good foundation for eventually moving to the full pistol (progressions I'll show at a later date).✅ . The 1st thing you need to learn how to do is hinge from the hips. The box touch down is a great way to learn this movement. Start by standing on a small box or weighted plate (usually 2 inches in height). Before you begin the squat, drive your hip backwards and bring your chest forward. This movement engages the powerhouse to your body (the posterior chain). Your bodyweight should feel completely balanced over the middle of your foot. Once the hip hinge is complete, begin to squat until the heel of your free leg taps the ground. After you have made contact, return to the start position. Make sure your knee stays in direct alignment with your toes during the entire movement. It should not rotate or collapse inwards whatsoever.👍🏻 . After you can do 20 reps in a row while completely balanced, start moving up the height of the box or set of plates. If you cannot do a smooth & balanced touch down from a height of 8 inches, your body is not yet ready to work on the full pistol. Solidify the fundamentals of the single leg squat first – THEN we'll work on the full pistol✅ . EVERY SINGLE PERSON should be capable of step 3! An inability to do so, means that your body has a major weak link that can easily lead to aches & pains down the road. I don't care if you are 15, 35 or 70 – you should be able to do a small single leg squat. Can you?! 🤔 . 🎵by @jookthefirst _________________________________ #Squat #SquatUniversity #Powerlifting #weightlifting #crossfit #training #wod #workout #gym #fit #fitfam #fitness #fitspo #oly #hookgrip #mobility #USAW #lifting #crossfitter
Elevated Pistol Squat
“This is a very tiny lift, standing on a box that’s two, four, maybe six inches high and you’re just doing a single-leg squat,” says Horschig. “Tap your heel and come back up. If your knee wobbles all over, that’s like an ‘Ah ha’ moment.”
Trying to hit a pistol squat without wobbling can be enough to stimulate the glutes, abductors, and other muscles to reduce knee valgus, but you can make things more advanced by doing a regular pistol squat while reaching one leg out to the side and the hands forward, like this:
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Poor knee control is one of the most common problems that create injuries & hold athletes back from producing to their potential. Here's one way to improve your knee control. 👇🏼 . The exercise shown today is called "Balance & Reach". This simple movement teaches you to engage your hips (the powerhouse to your body) & keep the knee in perfect alignment with your feet. To start, push your hips back & bring your chest forward. This is called a hip hinge. Next, as you squat down on 1 leg, simultaneously reach as far as you can WITHOUT your stance leg knee wobbling around!! You'll notice the further you try to reach, the harder it becomes to maintain knee stability. 🙌🏼 . Always stay in a pain-free range. For some, this means a very small movement to start out. I recommend trying 3 sets of 20 reps (we need high volume work to teach the body how to move correctly aka muscle memory). ✅✅ . 🎵 by @jookthefirst "Thoughts Free" 📲(Check it out on SoundCloud) _________________________________ #Squat #SquatUniversity #Powerlifting #weightlifting #crossfit #training #wod #workout #gym #fit #fitfam #fitness #fitspo #oly #olympicweightlifting #hookgrip #mobility #USAW #physicaltherapy #lifting #crossfitter #motivation #AskSquatU #squats #crossfitcommunity
Or you can try the following training method.
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One of the most common reasons an athlete may show a hip shift in the squat is due to a problem in coordination. An imbalance in strength/stability will lead the body to shift to one side vs the other. A great way to fix a hip shift, is to place the athlete into a vulnerable position (a single leg squat) and force them to fix their imbalance by teaching their body what they're doing wrong ✅ . RNT or reactive neuromuscular training is a way of teaching the body, not through verbal or visual instruction but through activities that improve proprioception or the sense of how the body is moving. By pulling the body into a bad position during a single leg squat, the athlete is forced to kick on certain muscles at the right time or else their body will collapse over 👊🏻 . In my experience, exposing and fixing these weak links in a single leg exercise is a great first step in fixing a hip shift in the conventional squat ✅ . For the full video (13 min long) on how to fix a hip shift in the squat with powerlifter @rbaylark – check out the link in my bio! ________________________________ #Squat #SquatUniversity #Powerlifting #weightlifting #crossfit #training #wod #workout #gym #exercisescience #fit #fitfam #fitness #fitspo #oly #olympicweightlifting #hookgrip #nike #adidas #lift #Crossfitter
Reactive Neuromuscular Training
This is a pistol squat with a band pulling the knee inward. The idea is to teach the body what a bad position is so it can learn to correct it — to teach it to feel for that collapse. It allows the body to turn on those glutes in the lateral side of the body and keep the knee stable and inline.
Doing exercises like this with enough repetition teaches the body to recognize and react to movements that are poor so it can stabilize the body when it trains again. It’s basically muscle memory.
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Knee cave during the squat & Olympic lifts is often in part due to poor hip strength & coordination. TAG SOMEONE WHO HAS THIS PROBLEM! This exercise is called Unilateral Abduction or ‘banded lateral kick-outs.’ To start place an elastic or rubber band around your ankles (I'm using a theraband here). Next assume an athletic single leg stance by pushing your butt back & bringing your chest forward slightly (hip hinge). This small movement allows us to engage our posterior chain and remain balanced. The cue I like to use for every squat (even small ones like this) to solidify this idea is: “squat with the hips – not with the knees.” Once we are in position, kick the non-stance leg out to the side and back in a slow and controlled manner. The distance the leg moves out to the side is not our main concern. Focus on keeping the stance leg in a stable and unwavering position during the entire exercise. A stable foot is essential to keeping the knee from moving around so jam your big toe into the ground and keep an arch in your foot! Recommended sets/reps: 2-3 sets of 10-15 reps before your squat workout. ___________________________________ Squat University is the ultimate guide to realizing the strength to which the body is capable of. The information within these pages are provided to empower you to become a master of your physical body. Through these teachings you will find what is required in order to rid yourself of pain, decrease risk for injury, and improve your strength and athletic performance. __________________________________ #Squat #SquatUniversity #Powerlifting #weightlifting #crossfit #training #wod #workout #gym #fit #fitfam #fitness #fitspo #oly #olympicweightlifting #hookgrip #mobility #USAW #physicaltherapy #lifting #crossfitter
Finally, you can consider doing a standing unilateral abduction with a band around the ankle and a small hinge at the hip. But there’s a twist: it looks like a strength exercise for the leg that’s kicking out to the side, but it’s actually a stability exercise for the standing leg.
“As you’re kicking out to the side with the free leg, your body’s getting a stimulus that for most people would allow the knee to cave in,” says Horschig. “So if you do enough of those reps, you’ll feel the lateral glutes of your standing leg clicking on to maintain stability.”
We’re not about to tell very elite, top 1 percent athletes to go back to basics and squat light until they figure out how to prevent their knee valgus but for the rest of us, it’s worth working on fixing this.
Remember, the problems caused by knee collapse don’t come all at once; they accumulate over months or years of training. That can be bad, because it means people can unwittingly train through the problem until it’s too late, but think of this article as good news: you have more control over knee valgus than you think.