It's the Quads...Until It's Not

Let’s get one thing straight—your knee isn’t some mysterious, delicate snowflake. It’s a pulley system. A pretty cool one, actually. And the boss of it all? Your quadriceps, the big muscle group on the front of your thigh.

Here’s how it works:

Your knee joint is a pulley-type system. The kneecap (patella) acts as the pulley, connected to the tibia (your shin bone) via the patellar tendon, and to your quadriceps via the quadriceps tendon. The main driving force behind this system is—you guessed it—the quadriceps. This system is what allows you to straighten your leg, walk up and down stairs, get off the couch, etc. If your knee is moving, it's doing something.

So if the quads aren’t doing their job—if it’s weak, undertrained, or just sleepy—your entire knee mechanism suffers. That’s where most people’s knee pain starts.

The Harsh Truth:

Weak quads = cranky knees.

This is why we say: It’s the quads… until it’s not.

Because step one when you’ve got knee pain isn’t to panic or immediately start Googling "meniscus tear."
It’s to ask: Are my quads strong enough to support this joint?

And if the answer is “ehhh... probably not,” guess what? That’s your starting line. If you passed strength tests and you know for a fact that your quads are strong enough, then you get permission to look at some other reason behind why your knees hurt.

Build strong quads. Restore proper movement at the knee. Build up your ability to perform the movements that put pressure on the knee.

Then—and only then—do you start looking at other possible culprits like joint damage, cartilage issues, or other deeper diagnoses.

So What Should You Do?

If your knee hurts, start with a solid quadriceps strengthening program. Things like:

• Heel-elevated goblet/front squats

• Step-downs

• Spanish squats

• Terminal knee extensions (TKEs)

Do this consistently, with good form, in a way that you don't compensate to use other muscles, and challenge yourself appropriately. Because here’s the deal:
You can’t skip over weak muscles and expect long-term joint health. The quads are your knee’s best friend—and sometimes, its only line of defense.

So until proven otherwise… it’s the quads.