Runner’s Knee: Causes, Key Tests, and Exercise Progression

Runner’s knee, also called patellofemoral pain syndrome (PFPS), usually causes pain around or behind the kneecap. It often shows up during or after running, on stairs, in squats, or when sitting with your knees bent for a long time.

The Journal of Sport and Health Science review found that PFPS was the most common running injury, accounting for 16.7% of running-related injuries. That’s one reason runner’s knee exercises matter: the right program can reduce stress on the knee joint instead of asking you to simply stop running and hope it goes away.

Most runner’s knee pain improves with targeted strengthening, training changes, and better control through the hip, thigh, and lower body. A physical therapist can help identify which factors are driving the pain and build a runner’s knee exercise program around them. 

Key Takeaways

• Runner’s knee usually causes pain around or behind the kneecap, especially with running, stairs, squats, or prolonged sitting.
• Common contributors include hip weakness, quad or glute imbalances, sudden changes in training routine, running mechanics, and poor lower-body control.
• The best runner’s knee exercises strengthen the glutes, hip muscles, quads, and hamstrings while keeping movement as pain-free as possible.
• Temporarily reducing mileage or intensity can help, but complete rest isn’t always the answer. 
• A physical therapist can assess biomechanics and build an exercise program that fits your pain, training load, and running goals.

Quick Navigation

• What Causes Runner’s Knee
• How to Know If It’s Runner’s Knee
• Warm-Up and Stretching
• Runner’s Knee Exercises: Phase 1
• Runner’s Knee Exercises: Phase 2
• How Physical Therapy Helps
• Return to Running

What Causes Runner’s Knee

Runner’s knee develops when the kneecap and surrounding tissues need to handle more stress than they can manage comfortably. The stress may come from changes in training, muscle imbalances, running form, or how the hip, knee, and foot work together.

Runner’s knee may be linked to: 

• Hip or glute weakness that lets the knee drift inward during running, squats, or step-ups.
• Quad weakness or imbalance that changes how the kneecap moves.
• Tight hamstrings, quads, or calf muscles that increase stress around the knee.
• A sudden jump in mileage, hills, speed work, or other high-impact training.
• Running form changes, such as a narrow step width, overstriding, or poor single-leg control.

Recovery usually starts by reducing stress on the knee, then building strength to handle greater loads over time.

How to Know If It’s Runner’s Knee

Runner’s knee usually causes pain at the front of the knee, around the kneecap, or behind it. The pain often gets worse with activities that bend and load the knee.

Common signs of runner’s knee include:

• Pain during or after running, especially downhill or after longer miles.
• Pain with stairs, squats, lunges, kneeling, or sitting with knees bent.
• A dull ache around the kneecap that may feel sharper with activity.
• Symptoms that improve with rest, but return when running volume increases again.

A physical therapist can check how your hip, knee, and foot work together using a single-leg squat, a step-down test, and strength testing. That assessment helps guide runner’s knee exercises that address what’s contributing to your pain. 

Warm-Up and Stretching

A short warm-up can help prepare your knee before strength work or a run. Gentle walking, easy cycling, or dynamic stretching can help your muscles feel ready to move.

Static stretches, such as hamstring or quadriceps stretches, may help if your muscles feel tight. Stretching alone usually isn’t enough to fix runner’s knee, but it can support a strengthening plan.

Runner’s Knee Exercises: Phase 1

Phase 1 focuses on calming symptoms and building control in the hip and thigh muscles. Stay in a pain-free range, and stop if pain increases during the exercise or lingers afterward.

Clamshells

Lie on your side with your knees bent and stacked. Keep your feet together and lift your top knee without rolling your hips backward. Slowly lower the top knee. Start with 10 to 15 reps per side.

Side-Lying Leg Lifts

Lie on your side with your bottom knee bent and your top leg straight. Lift the top leg a short distance while keeping your hips stacked and your body in a straight line. Slowly lower and switch sides.

Straight Leg Raises

Lie on your back with one knee bent and the other leg straight. Tighten the quadriceps on the straight leg, lift the leg to about the height of the bent knee, and slowly lower it. Try 10 reps per side.

Glute Bridges

Lie on your back with your knees bent and feet hip-width apart. Press through your heels and lift your hips until your body forms a straight line from shoulders to knees. Squeeze your glutes at the top, then lower slowly.

Runner’s Knee Exercises: Phase 2

Phase 2 adds more load once Phase 1 feels manageable and knee pain is improving. Keep the knee aligned over the foot, move slowly, and stay within a pain-free range.

Step-Ups

Stand in front of a low step with your feet hip-width apart. Place your right foot on the step, press through the whole foot, and step up without letting the knee collapse inward. Step down slowly, then switch sides.

Lateral Band Walks

Place a resistance band above your knees or around your ankles. Stand with feet shoulder-width apart and knees slightly bent. Step sideways with control, keeping your hips level and knees from caving in. Try 10 to 15 steps in each direction.

Bodyweight Squats

Stand with feet about shoulder-width apart. Sit your hips back, keep your knees tracking over your feet, and lower only as far as you can without knee pain. Slowly return to the starting position.

How Physical Therapy Helps

Physical therapy for runner’s knee turns the assessment into a plan. The goal is to reduce stress on the kneecap, build strength where it’s needed, and help your lower body handle running with better control. 

Physical therapy for runner’s knee may include:

• A runner-specific movement assessment to look at hip, knee, foot, and trunk control.
• Running analysis to review cadence, stride, foot strike, and other biomechanics.
• Training-load changes to reduce knee stress without losing more conditioning than necessary.
• A progressive strengthening program for the glutes, quads, hamstrings, and hip muscles.
• Guidance on return-to-running progressions, warm-ups, and pain-free exercise options.

Ivy Rehab’s athletic therapy services can help identify movement patterns that contribute to runner’s knee pain and build a plan around how you run. You can also learn more about runner’s knee treatment options if pain keeps coming back. 

Return to Running

Getting back to running works best when the knee can handle strength exercises, stairs, and daily activity without flaring up. For many runners, a run-walk plan is safer than jumping back into normal mileage.

A good starting point is 1 minute of running followed by 2 minutes of walking for a short, manageable session. If knee pain increases during the run or stays worse later that day, the load is probably too high.

Talk to a Physical Therapist About Knee Pain

Runner’s knee can be frustrating, especially when it disrupts your routine. The right exercise program can reduce knee stress, build strength, and help you get back to running with more confidence.

Find an Ivy Rehab location near you to connect with care close to home, or learn more about knee pain treatment and running analysis.