Runners are often faced with minor aches and pain throughout their running career, and running knee pain is a common hurdle runners face in their training. In most cases running knee pain can be corrected by proper sprint training, footwear and adequate rest.
One common source of pain for runners comes from the knees and can last for weeks, months and even years. It is known as patellofemoral pain syndrome (PFPS) and is referred more commonly as “Runners Knee”.
Runners knee has an insidious onset and can start out as an uncomfortable ache and progress over time to a sharp stabbing pain from the knee. It can manifest into a functional limitation in which running can no longer be done and can become a disturbance to normal activities of daily living.RELATED: RECOMMENDED PLANS FOR YOU
The Cause of Runner’s Knee:
Patellofemoral pain syndrome (PFPS) or runners knee is caused by multiple factors. PFPS is considered an overuse injury and is a combination of biomechanical, musculoskeletal, and inflammatory dysfunctions.
The anatomy of the knee comprises of the quadriceps muscle group(vastus lateralis, vastus intermedius, vastus medialis oblique or VMO, and rectus femoris), the patella(sesamoid bone commonly known as the knee cap), the hamstring muscles, the lateral and medial retinaculum of the knee(the spider web-like ligaments in which the patella sits in between), femur(thigh) bone and the tibia(shin) bones. The end of the femur bone creates the trochlear groove. In this groove the patella is able to move up and down when the knee straightens and flexes.
As long as the muscles and tendons surrounding the patella are balanced, the patella can move normally without difficulty or cause pain. The muscles on the femur create and absorb muscular forces during sports and activity.
During prolonged running the quadriceps muscles in the knee and hip are active. The muscles of the hip that are important to a runner are the gluteus medius and maximus, tensor fasciae latae(TFL) and the iliotibial band(IT-band).
Since running is an activity that can last for a prolonged period of time, these muscles are constantly working. Studies have proven that the muscles on the outside of the thigh and hip such as the IT-band, vastus lateralis, lateral hamstring muscles are more active than of the muscles in the inner and deeper part of the thigh and hip (VMO, gluteus medius and gluteus maximus)1,2. These hip stretches for runners are very helpful to balance out this strain.
When there is prolonged activation of the muscles on the lateral aspect of the thigh; the muscles become tight and over activated. This results in a loss of balance in the normal resting length of these muscles. When the muscles such as the TFL/IT band, vastus lateralis and the outer calf muscle (lateral gastrocnemius) become too tight they will negatively influence the position of the patella in the trochlear groove. As a result of these muscles becoming tighter; they will begin to cause a lateral translation force on the patella that will change its neutral position in the groove to move towards the lateral (outer thigh) side of the knee.
The muscles of the inner knee and thigh (the VMO, gluteus medius and gluteus maximus) will become under active. These muscles of the inner knee will become weak and will not stabilize the patella, thigh and knee properly2,3. The reason behind this is the underactive gluteal muscles (which have a minimal role during flat surface running) become weaker as they are not heavily relied on as other muscles such as the quads, calves, and TFL/IT-band muscle groups.
In regular ADLs, prolonged sitting causes the gluteal muscles to become even weaker as they are not needed in this position. This is common problem in many adults as we age and become weaker in the core muscles of the body.
Another reason may be the lack of running experience and specific sprint training. Studies have shown that professional runners (marathon runners, national competitors & 10+ years of experience) statistically suffer from fewer knee injuries including runner’s knee than those who are inexperienced runners5.
The VMO of the knee is a important patella stabilizing muscle2,3,4. When this muscle becomes weak, lateral tracking of the patella may result in increased “clicking” sensation and anterior knee pain3.
As a result of this muscular imbalance the knee has changed its mechanics and now relies on the already overactive knee muscles to provide all of its function of bending and extending as well as stability of the hip during running and normal walking. The angle of the patella to the ASIS of the pelvis is called the quadriceps angle (Q-angle).
In PFPS this angle is increased significantly and causes the alignment of the lower extremity to become internally rotated (the femur and tibia is rotated toward the opposite leg)4. As a result of this misalignment and muscular imbalance, the overactive muscles become overused.
The overuse of these muscles and tendons can become painful as the tissues become inflamed from the constant use during running. The insertion of the IT-band into the lateral retinaculum of the knee can become impinged2.
This impingement can begin as a dull ache and progress to sharp pain which is usually felt anterior to the knee1,2,3.In severe cases of PFPS, lateral subluxation/dislocation of the patella can be caused by prolonged lateral tightness of muscles on the outer thigh and calf and laxity of tissues on the medial aspect of the patella (medial retinaculum)3.
This is the reason why runner’s knee is considered an overuse running injury. As the knee is still engaged in running activity, the inflammation will continue and the symptoms of pain, clicking, and possible numbness will become progressively worse over time.
How to Fix Running Knee Pain:
During the Inflammation stage, pain and swelling can impede running and sporting activity. In this phase it is important to use the PRICE principle. PRICE is an acronym for Protect, Rest, Ice, Compression and Elevation. Icing 2-3 times a day for 10-20 minutes at a time will help reduce the tenderness and pain from the inflamed tendons.
Elevated the leg above the heart for most of the day especially during the earlier part of the day(morning-afternoon) will help keep the swelling and edema from forming in the knee’s joint line.
Compressing the knee with a ACE bandage while icing and elevating will give the best results in the control of pain and inflammation.
The athlete must immediately stop all running activity as this is causing symptoms to get worse. PRICE should be applied to the knee on a daily basis in the absence of running until pain and inflammation have subsided.
The runner must be willing to condition his/her body to the demands of running. In order to do that the muscle imbalance that has been created needs to be reversed so that normal knee mechanics can be done.
Since there are tight and weak muscles causing many of these mechanical problems, both of these problems need to be addressed simultaneously. Instead of ignoring running knee pain, be proactive and your knees will thank you!
The muscles of the lateral thigh include the TFL/IT-band, vastus lateralis, hamstrings and the gastrocnemius that are affecting the misalignment of the patella.
These muscles need to be stretched. The type of stretching can be done includes static, active or use of a foam roller for self myofascial release (SMR).
The foam roller can be used to inhibit the tight muscles of the TFL/IT-band complex. To use the foam roller, lie on the side of your involved thigh/hip so that the leg that is to be rolled is under you.
The roller should be positioned at the hip with the leg to be rolled totally straight. the other leg can be positioned in a flexed and externally rotated position.
Start by rolling the lateral thigh by moving your body in the opposite direction so that the roller rolls down towards the knee. When you encounter a tender spot/point, stop and try to hold it against the roller for 10 seconds to elongate the tight fibers. The ischemic pressure from the roller will release the tight fibers within the fascia surrounding the muscle6.
The roller can be used for the quads of the involved knee in the same manner. One or both of the thighs can be rolled at the same time. Start at just below the pelvis and roll distally toward the knee. Make sure to keep the thigh flat against the roller and using the weight of the body to provide the needed pressure. Stop at a tender spot holding for 10 seconds and then continue toward the knee joint. Do the same for the hamstrings and the gastrocnemius. Foam rolling muscle groups everyday will help decrease tightness and decrease the incidence of misalignment of the knee and hips.
The hamstrings may respond better to a static stretch. The most common stretch for the hamstrings is to elevate the foot on a step (6-8 inch), lock the knee out, pull the toes toward the head and slightly lean forward from your hips.
Keep the back fully erect. Stretch the hamstrings 3 times at 30 seconds a bout. Keeping the hamstrings flexible will reduce injuries such as strains during running.
Strengthening the weak muscles including the VMO, the gluteus medius, gluteus maximus and the core will enhance these muscle to enhance performance of the lower extremity as well as reverse the runner’s knee mechanical dysfunction.
An effective exercise to strengthen the VMO and the gluteus maximus is the squat. According to research, squatting up to 90 degrees of knee flexion will put too much stress in the patella femoral joint4.
It is recommended that the squat does not exceed 75 degrees of flexion during the down phase of the exercise. Activation of the muscles of the gluts will be activated fully without squatting to parallel from the floor.
The use of the physioball is an effective tool for doing squats. Control of the descent should be done with a 5 second duration before reaching the end of the squat(the down phase where the knees are flexed).
This will stress the eccentric strength of both the gluteal muscles and the VMO. Focus on trying to slide the butt under the ball during the squat. For greater VMO activation turn the feet outward during the squat.
Another exercise for strengthening the gluteus medius and maximus is Theraband walking. Theraband walking consists of an ankle sized resistance band that is placed at either above the knee, mid shin or ankle level(the higher the band is to the trunk the easier the exercise is, the opposite is true of increasing the exercises difficulty). Utilize the resistance band further by trying this resistance band workout.
This exercise trains the gluteus medius and maximus muscle. Lateral walking or shackle walks can be performed by walking sideways over a distance of 10-15 feet in one direction and then repeat the same distance in the opposite direction.
Forward and backward walking (monster walks) is another variation to shackle walking and can be performed at the same distance.
3. Integrated Sprint Training: barefoot running
Several studies in barefoot running have shown many advantages when doing sprint training without using regular sneakers. One advantage with running barefoot is the development of the intrinsic muscles in the foot.
When a runner is training with their sneaker on; these foot intrinsic muscles are predominantly turned off. This makes the sensory input coming from the ground to the foot difficult to be able to correctly position the foot during foot strike.
Improper foot strike (i.e. heel striking or flat foot contact) will throw the mechanics off and decrease speed and increase braking forces6. The intrinsic foot muscles support the arch of the foot. The arch of the foot contributes to a “spring like” force. If the intrinsic muscles are developed, the arch of the foot will become stronger and would increase the push off from the ground.
Another key fact is that elite runners have a longer stride length and flight time versus non-elite runners. In training, the runner should incorporate several miles at a specific time limit of barefoot running versus using running shoes. This will help with the development of intrinsic muscles, increase absorption forces within the relationship from the foot hitting the ground.
A technique to teach running technique is the using a speed ladder. A speed ladder can help teach the runner to strike the ground with the ball of the foot rather than the heel.
By perfectly placing the ball of the foot in each ladder space, the runner will not only be able to build the intrinsic muscles of the foot, but also learn proper foot mechanics as far as proper foot position with regards to the rest of the body.
Practicing these running drills with the speed ladder and barefoot running will help decrease any abnormal loading of the lower extremity because of incorrect foot striking positions and decreased pain bad positioning of the lower extremity during running.
Developing good, responsive foot intrinsic strength will decrease absorption of forces from the ground into the tibia and knee, which causes muscle imbalances and ultimately; runner’s knee pain. Runners looking to further improve their running can check out WatchFit’s Running plans, runners of all experience can find guidance, from our beginning running plan to intermediate and advanced running plans.
1. Presswood L, Cronin J, Keogh JWL, Whatman C. Gluteus Medius: Applied Anatomy, Dysfunction, Assessment, and Progressive Strengthening. Strength & Cond. 2008: 30 (5); 41-53
2. Callado H, Fredericson M. Patellofemoral Pain Syndrome. Clin Sports Med 2010: 29; 379-398.
3. Lininger MR, Miller MG. Iliotibial Band Syndrome in the Athletic Population: Strengthening and Rehabilitation Exercises. Strength & Cond. 2009: 31 (3); 43-46
4. Bolgla LA, Malone TR, Umberger BR, Uhl TL. Hip Strength and Hip and Knee Kinematics During Stair Descent in Females With and Without Patellofemoral Pain Syndrome. JOSPT 2008: 38(1); 12-18
5. Piva SR, Goodnite EA, Childs JD. Strength around the Hip and Flexibility of the Soft Tissues in Individuals With and Without Patellofemoral Pain Syndrome. JOSPT. 2005: 35(12); 793-801.
6. Lieberman DE. What We Can Learn About Running from Barefoot Running: An Evolutionary Medical Perspective. Exerc. Sport Sci. Rev. 2012: 40(2); 63-72