Why Do Planks Hurt My Knees? (4 Factors to Consider)

Ever wondered, “Why Do Planks Hurt My Knees?”

Planks are without doubt a great core exercise.

Plus, they are relatively simple to perform.

And yet, they don’t come without their problems.

One such issue seems to be that some of you may experience knee pain either during or after performing planks.

So, what exactly is going on here?

Why Do Planks Hurt My Knees?

Your knees shouldn’t be locked out (completely straightened) during planks. If you squeeze your quads during planks without also contracting your glutes and hamstrings, your knees will straighten out, which can cause you pain. Excessive quadricep contraction can occur if you rest on your toes rather than the balls of your feet. You can also try the push up-position plank, which is an easier variation than elbow planks. By doing so you will generally find it easier to contract the glutes during planks.

1. You’re Locking Out at the Knees

The main reason that planks hurt your knees is because you’re locking out at the knees.

This shouldn’t be confused with “locked knees”, which is the inability to actually straighten the knee.

However, you may find that during planks your knees are completely straight, which is generally the cause of your discomfort.

The main reason this occurs is because you’re trying to keep your entire body tight and contract as many muscles as possible.

Now, initially this may seem like a good thing and the correct way to perform a plank.

With that being said, when you contract the quadriceps you will automatically straighten the knee.

Obviously, your legs are extended during planks, and I do agree the quads should be contracted.

However, as soon as the knees straighten, this tells me that your focus for the plank is placed entirely on the front of the body.

Basically, you are using the plank as an ab exercise and not as a core exercise.

There are various core muscles at the back of the body too.

And these play just as important a role during planks.

2. You’re Not Contracting Your Glutes

So, I‘ve just mentioned the back of the body, and this could be the solution to your knee discomfort.

You must contract the glutes while planking.

In fact, I would go as far to say that the main two muscle groups that you should really squeeze tight during planks are the glutes and the abs.

And it just so happens that these are antagonistic (opposing) muscle groups too.

As soon as you contract the glutes this will also engage the hamstrings.

And as the hamstrings are the opposing muscles to the quads, this will limit any excessive force you place on the quadriceps.

Basically, this will ensure that your knees aren’t fully straightened out.

Another benefit of contracting the glutes is that this will ensure that your hips remain high.

One of the most common planking mistakes is allowing the hips to sag, which unfortunately defeats the object of working the abs and core muscles.

Furthermore, when you allow your hips to sag you will no longer have a neutral spine.

This will of course place more pressure on your lower back, as well as your shoulders.

So, you could say that bringing your glutes to the planking party is a win-win.

The TRUTH About Planks (It’s UGLY)

3. Rest on the Balls of Your Feet (Not Your Toes)

Something else to consider if your knees hurt from planking is how your feet are placed on the floor.

I know this is probably not something that you have ever thought about before, but it can make a huge difference.

Most of us will plank while resting on the tops of our toes.

However, when it comes to contracting the various muscles of the body this could cause you to excessively tighten the quads, while ignoring the glutes and hamstrings.

And this of course will lead to you locking out your knees.

The result will be that you end up placing additional stress on the knees.

You should actually shift your weight ever so slightly so that the balls of your feet are in contact with the ground.

This will immediately bring the hamstrings and glutes into the equation.

Plus, it will be easier to remain relaxed at the knee joint.

I will admit that if you have been planking “on your toes” for an extended period of time you may find it difficult to adjust to this new foot position.

Basically, your focus will shift from actually contracting the target muscles and worrying about whether your feet are in the right position.

However, with practice, once you get used to resting on the balls of your feet you’ll immediately notice that the pressure on your knees has been relieved.

4. Try the Push Up-Position Plank

I would hazard a guess that most of us get into the elbow plank position when we first start out with the exercise.

So, your forearms are in contact with the floor.

This is what most of us would consider the standard plank position.

However, the plank is actually an extremely versatile exercise, and there are many variations for you to try out.

In fact, you can target different areas of the core, and the body in general, by performing various planks.

If you’re struggling with knee pain you could always try the push up-position plank.

So, your hands would be on the ground rather than your forearms.

In effect, you are holding the top position of the push up.

This is actually a slightly easier variation, but it still targets the core muscles extremely well.

Furthermore, as your body is angled slightly upwards from feet to head you’ll actually take some of the pressure off the quadriceps.

Plus, it’s easier to bring the glutes and hamstrings into the equation from this position.

And we now know that the more your glutes and hamstrings are involved, the easier it will be on your knees.

So, if you’re experiencing discomfort in your knees from planks, there are plenty of alternatives for you to try.

22 Plank Variations

Final Thoughts

So, I hope you now have a better understanding of why planks could potentially be hurting your knees.

The main reason will be that you’re completely locking out at the knees.

This typically occurs because all the pressure is focused on your quads, plus you’re not contracting your glutes.

You should also try to shift your weight onto the balls of your feet rather than the toes.

This once again will release some of the stress placed upon the quads and bring the glutes and hamstrings more into play.

Finally, if you want to continue planking, but feel discomfort from the “traditional plank” then try the push up-position plank.

Yet again, this will bring more focus onto the glutes and hamstrings, while also making it easier to rest on the balls of your feet.

Next, I’ve also written about one of the majr planking problems. So, take this opportunity to learn more about why you can’t feel planks in your abs.