How to Fix Runner’s Knee

What Are the Best Exercises for Patellofemoral Pain? (aka Runner’s Knee)

A Guide to Treating Runner’s Knee, by Expert Orthopedic Physical Therapists

Runner’s Knee (also called patellofemoral pain syndrome | PFPS) is the most common running injury we treat. So, why do runner’s develop Runner’s Knee in the first place? And how do we treat clients with Runner’s Knee? We’ll show you exactly how to fix Runner’s Knee here!

How is Runner’s Knee diagnosed?

Runner’s Knee is specifically located in the anterior knee (see image below). It is sometimes described as being felt underneath the kneecap as well.

We find that training error is commonly the reason why runner’s develop Runner’s Knee. Training error includes sudden increases in mileage, frequency of runs, intensity of runs, etc.

What are some of the biomechanical findings associated with Runner’s Knee?

A sudden introduction of downhill running is also associated with the development of Runner’s Knee because downhill running increases the load on the patellofemoral joint. This study assessed the biomechanics of uphill and downhill running, showing that downhill running resulted in adopting an increase in heel strike. Greater heel strike results in more of the ground reaction forces being transmitted to the knee joint. 

Below is a running technique checklist we use to determine who is at risk for developing Runner’s Knee:

1. Cadence: increase by 5-10% if you have knee pain with running, especially if your self-selected step rate is less than 160 steps per minute. This study showed that increasing cadence (steps per minute) significantly decreases knee joint load when running.

2. Shin Angle: avoiding an extended shin angle when landing is important because it’s associated with overstriding and excessive knee strike. According to this study rearfoot strikers experience greater knee load than forefoot strikers. With that said, we do not coach our clients to alter their self-selected strike pattern, as it increases biomechanical stresses on different parts of the body. For example, switching to a forefoot strike pattern can leave us subject to other injuries, such as Achilles tendonitis and metatarsal stress fractures. 

Extended Shin Angle

Vertical Shin Angle

3. Foot Inclination Angle: this is the angle between the ground and the sole of your foot. A greater foot inclination angle results in greater knee loading. You want to attempt to land with a lower foot inclination angle if you’re experiencing knee pain while running (see image below).

High Foot Inclination

Neutral Foot Inclination

See this video below for a better understanding on these mechanics:

And here is how we work on increasing running cadence in those who have a low cadence:

Quadriceps Weakness is Associated with Runner’s Knee

According to this systematic review, weaker knee extensor strength, as expressed by peak torque, is a risk factor for PFPS. We know that isometric exercises can reduce pain and increase muscle activation in the quads in those with knee pain, as noted in this study by the British Medical Journal. Therefore, we like to start with some isometric exercises to recruit the quads and decrease pain. These exercises can be performed daily. Below are a few examples of isometric exercises that we prescribe:

Isometric Quad Exercises

We need to also include exercises that load the quadriceps through range (aka concentric and eccentric loading). These exercises are runner specific and will adequately prepare the patellofemoral joint to accept load while running. These exercises are to be performed every 2-3 days, depending on recovery and pain sensitivity. Here are some examples.

Bulgarian Split Squats

Skater Squat

Reverse Lunge to Runner’s Pose

We can manipulate the variables of these exercises by increasing the height of the step, adding additional weight, or adjusting the angle of the movement to load the knee joint more than the hip joint.

Lateral & Forward Step Down

Single Leg Eccentric Step Downs

Hip Dominant & Knee Dominant Lateral Step Down

Hip Strength is Associated with Runner’s Knee

This study found that patellofemoral pain syndrome (PFPS) is associated with decreased hip strength, specifically at the abductors and external rotators.

This systematic review suggests that a combination of hip and knee strengthening is more effective at treating patellofemoral pain than knee strengthening alone. Below are some examples of hip abductor and external rotator exercises that we prescribe to treat Runner’s Knee.

Copenhagen Plank Variations

Single Leg RDLs

Bridge with March

Muscle Tightness and Joint Restriction is Associated with Runner’s Knee

Ankle Dorsiflexion Range of Motion

This study demonstrated that a lack of ankle dorsiflexion can cause an increase in dynamic knee valgus (knee caving inward), which can cause excessive strain on the knee joint. We assess ankle dorsiflexion as can be seen below:

How we assess

Some ankle mobility drills

Quadriceps, Hamstring, Hip Flexor and Calf Flexibility

We also assess flexibility of these muscles and assess between sides. If there is an asymmetry that is associated with the injured side, we add these stretches into the program for 3 sets of 30-60 seconds, twice per daily, 5-7 days per week.

Half Kneeling Quad/Hip Flexor Stretch

Hamstring Stretch

Calf Stretch

How Long Will It Take For Runner’s Knee to Improve?

Following a good rehab program will typically allow you to get back to running within a few weeks (6 weeks), depending on the severity and chronicity of your injury. We are sure to incorporate cross training techniques to maintain as much cardiovascular fitness as possible. That can include rowing, swimming or elliptical.

We make sure to incorporate a walking program into our clients’ exercise prescription. We find the amount of time that is tolerated and work up from there. Once our clients can walk for > 60 minutes with minimal to no knee pain, we begin a run:walk protocol. The protocol starts at 1 minute of walking and 1 minute of running for 5 cycles. We increase the number of cycles first, then we manipulate the ratio (2:1 of run:walk, 3:1 of run:walk, then 4:1 of run:walk, then 5:1 of run:walk). We work up towards 30 minutes of run:walk. Once the runner is capable of run walking for 30 minutes at a 5:1 ratio, we begin running without walking breaks. This process can take an additional 6 weeks, so we typically see our running clients with Runner’s Knee 1-2x/week for a total of 12 weeks.

Closing Remarks

We hope you found this article helpful. If you are a runner experiencing Runner’s Knee, and want to learn more, read about our running analysis process.

If you would like to work with us to resolve your Runner’s Knee pain, click below to speak with a physical therapist.

Disclaimer: This is not intended to be formal medical advice. Your individual needs should be met by the appropriate health care practitioners. Please consult with a trusted provider.

Dr. Paul Nasri, PT, DPT, OCS, COMT

Doctor of Physical Therapy

The Game Plan Physical Therapy