16 Sep Are squats bad for your knees?

There’s no shortage of myths out there when it comes to exercise. Many have been busted, but there’s one that simply refuses to die; “squats are bad for your knees”.

But are they really?

Are squats bad for your knees?

Research would respond with a big fat NO. In fact, squatting may even be very good for your knees. Don’t believe me? Let’s look at the science…

A common misconception is that as you squat, your anterior cruciate ligament (ACL) is placed under tension, making it susceptible to damage. However, research has shown that the opposite is true. See, the force placed on this ligament decreases the more your knee is bent — which is exactly what happens when you squat.

Now, this isn’t to say that there’s no load placed through the knee as you squat.

In fact, as you squat, there’s an increase in shear stress through many of the passive structures of the knee (including your meniscus, cartilage, and patella tendon). But the key is that this force peaks as you reach 90 degrees of knee flexion — after which it appears to remain around the same, or even decrease.

To provide a bit of context, 90 degrees of knee flexion refers to the point when your thighs become parallel to the ground.  This is about the same degree of flexion as when you walk up the stairs.

So with this in mind, it’s safe to say that the squatting movement itself is not bad for your knees.

But what about squatting under load?

This is where things get a little bit interesting (or at least I think they do…).

Obviously, during a gym session, squats aren’t always performed just with your body weight. Over time, you will progress to squatting under load.  That load will gradually increase to accommodate increases in strength and function. As load increases, the force distributed through the knee joint also increases.

But this is not necessarily a bad thing.

In fact, I would argue that it is a very good thing.

Is squatting good for your knees?

Just like the muscles in your legs, the passive structures within your knee (cartilage, ligaments, tendons, and meniscus) all have the capacity to adapt and become stronger. As you gradually expose them to increasing loads over time, they get stronger, making them less prone to injury.

For this reason, the squat one of the best exercises on the planet for improving knee joint health.

However, there are a few caveats around this:

1) Your exercise technique needs to be sound
2) The increases in load must occur in a gradual and safe manner

How to Squat Properly

The key to getting all the benefits of squatting come from performing the movement with good technique.

So, without further ado, my step by step approach to squatting with good technique:

• Set yourself up with your feet a bit wider than shoulder width, with your toes pointed out slightly. Your entire foot should be making contact with the ground, and your big toes should be pressed firmly into the floor.
• Keeping your chest up tall, proceed to sit straight down so that your bum drops back and down (this should be done slowly, and under control).
• Hold a slight pause at the bottom without losing your chest position. Your torso should be upright, your spine straight, and your hips flexed to about 45 degrees (give or take).
• From here, push your feet into the ground until you are back at your starting position.

Simple stuff really.

Some squatting FAQs

Is it OK to squat below parallel? Squatting below parallel is a great option if you have the mobility to do so. It’s this movement that takes your knee through a full range of motion, which helps improve knee health. If you don’t have the mobility available, then it’s worth doing some dedicated mobility work.

What if my knees go in front of my toes? If your knees didn’t have the ability to travel over your toes, you wouldn’t be able to walk. Seriously, you are in this position every day, so why not train to become stronger in this position?

Progressing the Squat

Adding load is crucial to improving strength, joint health, and function. But it’s important to do this slowly and safely. Here’s how to progress your squat to allow the gradual addition of load:

• Plate squat (Weeks 1-4).
• Goblet squat (Weeks 5-8).
• Dual KB front squat (Weeks 9-12).
• Front Squat (Weeks 13-16).
• Back Squat (Weeks 17-20).

After each 4-week period, you should have mastered that specific variation. Each week you should also increase the weights you use slightly to continually increase strength throughout the entire duration of the progression.

I appreciate that this may look like a lengthy process, but it’s important to make sure that progression is done as safely and as efficiently as possible.

Take Home Message

Squats aren’t bad for your knees. In fact, when done properly, they are really beneficial for knee health.

If you’re new to squatting or have previously had an injury, it’s always a good idea to have an expert check your technique. To find a university-qualified exercise professional near you, click here.

Written by Hunter Bennett. Hunter Bennett (PhD) is an Accredited Exercise Scientist, Strength Coach at BUILT Strength and Conditioning, and Lecturer at the University of South Australia. Follow his research at ResearchGate and read more of his work at the BUILT Blog.