Runner’s Knee: Why Your Knee Hurts (And Why Rest Alone Usually Isn’t the Answer)

If you’ve ever felt pain around or behind your kneecap during a run, going down stairs, squatting, or after sitting for a long time, you’re not alone. One of the most common injuries I see in runners is runner’s knee, also known as patellofemoral pain syndrome (PFPS).

The good news? It doesn’t mean your knees are “bad,” and in most cases, you don’t need to stop running completely.

What is Runner’s Knee?

Runner’s knee is pain that develops around or behind the kneecap when the forces going through the knee exceed what the tissues can currently tolerate.

Contrary to popular belief, the pain usually isn’t caused by your kneecap being “out of place.” Instead, it’s often the result of a combination of training errors, muscle weakness, movement patterns, and recovery.

Common Symptoms

You may have runner’s knee if you experience:

• Pain around or behind the kneecap

• Pain during or after running

• Discomfort going down stairs or hills

• Pain with squats or lunges

• Aching after sitting for long periods (“movie theater sign”)

• Stiffness when first getting up after sitting

Why Does It Happen?

There usually isn’t one single cause. Instead, runner’s knee develops when multiple factors add up over time.

Common contributors include:

1. Training Load

One of the biggest reasons runners develop knee pain is doing too much, too soon.

This might include:

• Increasing mileage too quickly

• Adding speed work too fast

• Running more hills

• Returning after time off without rebuilding gradually

Your tissues need time to adapt to increased demand.

2. Hip and Glute Weakness

Your hips help control the position of your leg when your foot hits the ground.

If the glutes aren’t doing their job efficiently, the knee often ends up taking more load than it should.

This doesn’t mean weak glutes are always the cause, but improving hip strength is frequently part of a successful treatment plan.

3. Quadriceps Capacity

Your quadriceps absorb a tremendous amount of force every time you run.

If they aren’t strong enough—or aren’t prepared for your current training load—the front of the knee can become irritated.

4. Running Mechanics

Small changes in running form can sometimes reduce stress on the knee.

Depending on the individual, this may include:

• Increasing cadence slightly

• Adjusting stride length

• Improving trunk or hip control

Not everyone needs gait changes, but when appropriate, they can be a valuable tool.

5. Recovery

Sleep, nutrition, stress, and recovery all influence how well your body adapts to training.

Sometimes the issue isn’t that you’re training too hard—it’s that your body isn’t recovering enough.

Should You Stop Running?

Not necessarily.

Many runners can continue running while recovering if their symptoms stay within an acceptable range.

A common guideline is:

• Pain does not increase by 3/10 or less from your current level of pain during the run

• Pain doesn’t progressively worsen

• Symptoms return to baseline within 24 hours

Temporary modifications—such as reducing mileage, avoiding hills, or decreasing intensity—often allow healing while maintaining fitness.

What Actually Helps?

A successful rehab program usually includes:

• Progressive strengthening for the glutes, quadriceps, calves, and hamstrings

• Single-leg stability training

• Gradual exposure back to running

• Training load management

• Running gait assessment when indicated

• Mobility work when needed (not just endless stretching)

Every runner is different, so treatment should be individualized rather than relying on generic exercises from the internet.

My Go-To Strength Exercises

Some of my favorite exercises for runners with knee pain include:

• Spanish squats

• Split squats

• Step-downs

• Single-leg Romanian deadlifts

• Lateral band walks

• Calf raises

• Single-leg balance progressions

The best exercise is the one that’s appropriate for your current strength and irritability level.

When Should You See a Physical Therapist?

If your knee pain:

• Has lasted more than a couple of weeks

• Keeps returning every training cycle

• Is changing the way you run

• Prevents you from reaching your goals

…it may be time for an individualized assessment.

At Empowered Stride PT & Performance, I don’t just treat your knee—I evaluate the entire movement system, your training, and your running mechanics to identify why the pain developed in the first place.

Together, we’ll build a plan that helps you return to running stronger, more confident, and with fewer setbacks.

Pain doesn’t have to be part of being a runner. With the right plan, most runners can get back to doing what they love—stronger than before.