Knee Noises: Knee Popping When Squatting | Good or Bad?

If you've been squatting long enough, you've probably had this happen.

You descend into a squat, everything feels normal, and somewhere near the bottom you hear it.

Pop.

Or maybe it's more of a click, crack, or snap.

Your first thought usually isn't, “That's interesting.”

It's, “What was that?”

I've heard lifters worry about knee noises for years, and I understand why. When you're standing under a loaded bar and something inside your knee suddenly makes a sound, it's easy to assume that sound means damage.

But knees make noise.

So do shoulders, hips, ankles, and just about every other joint you've been using for a few decades.

The important distinction isn't simply whether your knee pops when you squat.

It's what happens along with the pop.

The First Question I Ask: Does It Hurt?

This is where I'd start.

If your knee occasionally pops or clicks during a squat but there is no pain, swelling, instability, or change in how the knee moves, that's very different from a knee that suddenly pops and hurts.

Sound by itself doesn't tell you very much.

What gets my attention is when the sound comes with something else.

Pain.

Swelling.

Locking.

A knee that suddenly feels unstable.

A feeling that something catches at exactly the same point during every repetition.

Those are different situations from the occasional painless crack you hear when you're warming up.

Why Do Knees Pop When You Squat?

There isn't one single reason.

Your knee is a moving joint surrounded by cartilage, tendons, ligaments, muscles, and joint fluid. When you squat, all of those structures have to work together as the knee moves through a large range of motion under load.

Sometimes that movement makes noise.

One common explanation for painless popping is cavitation.

It's similar to what happens when you crack your knuckles. Changes in pressure inside the joint can cause gases within the joint fluid to form or release, producing the pop you hear.

If you've ever dropped into a squat, heard one good crack, and then couldn't reproduce it on the next five reps, you've probably experienced something along those lines.

There was a sound, but nothing else changed.

Sometimes It's More of a Snap Than a Pop

Not every knee noise comes from inside the joint itself.

Tendons and other soft tissues move as you bend and straighten your knee. As the knee travels through its range of motion, those tissues can shift over nearby structures and create a clicking or snapping sensation.

You may notice it only at a certain depth.

Maybe everything is quiet until you get below parallel. Maybe you hear it during the first few warm up sets and then it seems to disappear once you've been moving for a while.

I've also seen lifters become much more aware of knee noises after they start squatting deeper than they're used to.

You're taking the joint through positions it hasn't spent as much time in, so suddenly you're noticing sensations and sounds that weren't obvious before.

This video does a good job explaining knee clicking, what may be contributing to it, and when it should actually concern you:

If muscle imbalances or movement issues are contributing to the clicking, working on those should be the priority. That's the part you don't want to ignore just because you've found something that makes the knee feel better.

For training in the meantime, however, one of the simplest things you can try is wearing knee sleeves.

The compression helps keep the knee warm and can provide a more supported, stable feeling as you squat. Many lifters also find that keeping the joint warm throughout a session makes their knees feel smoother as they move through repeated flexion and extension.

I wouldn't look at sleeves as something that fixes the underlying cause of the clicking. Think of them as a way to maintain warmth, add compression, and give the knee some extra support and feedback while you work on whatever may actually be contributing to the problem.

If the issue seems specific to one movement, it's also worth understanding why squatting and lunging can feel different at the knee.

Why Your Knees Can Sound Worse at the Beginning of a Workout

This is something a lot of lifters notice.

You walk into the gym, do your first few bodyweight squats, and your knees sound like somebody stepping on bubble wrap.

Then you warm up for ten minutes and suddenly they're much quieter.

That's one reason I don't like judging how my knees feel from the first squat of the day.

Give them some movement first.

Start with a few minutes of general activity. Work through comfortable knee flexion and extension. Do some bodyweight squats. Then gradually add load instead of jumping straight into your working weight.

The goal isn't to perform some magical warm up that makes every click disappear.

It's to give your body a chance to transition from sitting at a desk, driving a car, or walking around all day into handling loaded squats.

When Knee Popping Is Usually Less Concerning

I've had my own joints make enough noise over the years that the sound alone doesn't bother me much anymore.

What matters is the pattern.

An occasional pop that isn't painful, doesn't cause swelling, doesn't change your movement, and doesn't leave the knee feeling unstable is very different from a sudden painful event.

The same goes for clicking.

Some people have knees that click through certain portions of the movement almost every time they squat.

If it's been happening for years, doesn't hurt, and hasn't affected how the knee functions, the sound itself isn't necessarily telling you that something is being damaged every repetition.

You don't need perfectly silent knees to have healthy knees.

When I'd Pay More Attention

There is another side to this.

If you hear a pop during a squat and immediately feel sharp pain, that's not something I'd just ignore and keep loading.

The same applies if the knee starts swelling afterward, feels unstable, locks, gives way, or suddenly loses range of motion.

I'd also pay attention if something changes.

Maybe your knee has always clicked painlessly, but now that same click is accompanied by pain.

Maybe you've developed a new catching sensation that happens at exactly the same point during every rep.

Maybe you had one significant pop under load and the knee hasn't felt right since.

That's when I'd stop treating it as normal gym noise and have it properly assessed by a qualified healthcare professional.

Don't Let the Sound Change Your Squat

This is something I've seen happen more than once.

A lifter hears a knee click.

Nothing hurts.

But now they're thinking about it.

On the next rep, they shift their weight away from that knee. Then they change their stance. Then they stop letting the knee travel naturally. Before long, they're squatting completely differently because they're trying to avoid a sound.

If there is no pain or other symptom telling you something is wrong, don't automatically rebuild your entire squat around a click.

Pay attention to how the movement feels.

Keep your feet stable, control the descent, let your knees track naturally with your toes, and use a range of motion you can control.

The goal is a strong, repeatable squat, not a silent one.

A Good Warm Up Doesn't Need to Take 30 Minutes

I think lifters sometimes overcomplicate this too.

You shouldn't need an entire second workout before you're allowed to squat.

The purpose of the warm up is to get warm, move the joints you're about to use, practice the movement, and progressively introduce load.

For squats, that can be pretty simple.

Get your body moving.

Do some unloaded squats.

Work through whatever hip and ankle movement you personally need.

Then start with the empty bar and progressively build toward your working weight.

If your knees feel dramatically different after you've done that, that's useful information.

It's also why I wouldn't panic because your knees sounded like a bowl of Rice Krispies during the first three bodyweight squats of the morning.

What If My Knees Pop Every Time I Squat?

This is where people tend to worry a little more.

Once or twice doesn't bother them. But when the knee clicks at the same point on almost every squat, they start wondering whether something is wearing away inside the joint.

Frequency alone still doesn't tell the whole story.

If your knee has clicked at roughly the same point for years without pain, swelling, locking, or instability, that's very different from a new clicking pattern that appeared yesterday and hurts every time it happens.

I'd pay more attention to changes than noise alone.

Is this new?

Does it hurt?

Is the knee swollen?

Does it feel unstable?

Has your range of motion changed?

Does something feel like it's mechanically catching?

Those questions tell you much more than simply counting how many times the knee clicks.

Should You Stop Squatting If Your Knees Pop?

Not simply because they make noise.

If squatting is painless, your knee feels stable, and nothing else has changed, an occasional click or pop by itself isn't necessarily a reason to stop training.

I'd still pay attention to it.

Warm up properly. Watch your movement. Don't suddenly increase your squat volume, load, and depth all at once and then wonder why your knees are talking to you.

But you don't need to become afraid of bending your knees just because they make noise.

If the popping is accompanied by pain, swelling, instability, locking, or a sudden change in how your knee functions, that's different.

At that point, I'd stop trying to solve the problem by changing your stance every five minutes and get the knee properly assessed.

There is a big difference between respecting a symptom and becoming afraid of a sound.

What I've Learned About Noisy Knees

The longer you're around strength training, the more you realize the human body isn't a silent machine.

Joints crack.

Tendons move.

Knees click.

Sometimes you stand up after sitting for an hour and your entire body sounds like someone dropped a bag of gravel.

What I've learned is not to judge a joint by sound alone.

Pay attention to what comes with it.

If your knee pops during a squat but feels completely normal before, during, and after the movement, that's very different from a knee that pops and immediately becomes painful or unstable.

Warm up properly. Pay attention to your technique. Build your squat gradually. Work on obvious movement issues or muscle imbalances rather than trying to hide them.

And if warmth and compression make your knees feel better while you're doing that, there's nothing wrong with using them.

But don't assume every click means you've damaged something.

Your knees don't need to be silent. They need to work.

Frequently Asked Questions

Why does my knee pop when I squat?

Knees can pop or click during squats for several reasons, including pressure changes within the joint and movement of tendons or other tissues as the knee bends. The sound alone doesn't identify the cause.

Is knee popping when squatting bad?

Painless popping without swelling, instability, locking, or a change in function is generally different from a painful pop. A pop accompanied by other symptoms deserves more attention.

Why do my knees crack when I squat but don't hurt?

Joints can make noise without pain. Pressure changes inside the joint and movement of surrounding tissues can both create sounds during knee flexion. If the cracking is painless and your knee otherwise feels normal, the sound itself may not indicate a problem.

Why do my knees pop more when they're cold?

Many lifters notice more clicking and stiffness at the beginning of a workout and less once they've been moving. A gradual warm up can make the knees feel more comfortable before heavier squat sets.

Do knee sleeves stop knees from popping?

Not necessarily. Knee sleeves provide warmth and compression around the knee, and some lifters find their knees feel smoother or quieter while wearing them. They shouldn't be treated as a fix for unexplained painful popping.

Should I squat if my knees are clicking?

If the clicking is painless and your knee feels stable and functions normally, the sound alone isn't necessarily a reason to stop squatting. Clicking accompanied by pain, swelling, locking, instability, or a sudden change in function should be evaluated appropriately.

When should I worry about my knee popping?

Pay more attention when a pop is associated with sharp pain, swelling, instability, locking, loss of motion, or a significant change from what you normally experience. A sudden painful pop under load is different from occasional painless joint noise.

References

1. Protopapas MG, Cymet TC. Joint cracking and popping: understanding noises that accompany articular release. J Osteopath Med. 2002;102(5):283-287.

2. de Oliveira Silva D, Pazzinatto MF, Del Priore LB, et al. Knee crepitus is prevalent in women with patellofemoral pain, but is not related with function, physical activity and pain. Phys Ther Sport. 2018;33:7-11.