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What is runner’s knee?

Patellofemoral Pain Syndrome (PFPS) or runner’s knee is a general term for a number of conditions that cause pain from the patellofemoral joint and the surrounding tissues. This joint is the intersection between the kneecap (patella) and the thighbone (femur). Those with runner’s knee may feel a burning sensation or a dull ache under and around the kneecap. Some people also experience swelling as well as a cracking, popping or grinding sensation.

Runner’s knee is usually created by muscle weakness or tightness around the leg, causing the patella to bump against the femoral groove (end of the femur). Occasionally, the pain may be due to torn cartilage or strained tendons. As the name suggests, runner’s knee is prevalent in runners but it is also caused by other high impact activities such as skiing, jumping or squats.

How do I avoid getting runner’s knee?

Increase your training gradually

Avoid dramatically increasing your training volume and intensity. The mileage and duration of your runs should be built up incrementally. The general rule of thumb is that you should never increase your training volume by more than 10% each week. This allows the body time to recover and adapt[1].


For example,

  • Week 1: 20 minute run

Increase by 10%

  • Week 2: 22 minute run

It is also important to give your knees a rest day between runs. Instead of running, participate in a low-impact activity such as swimming, cycling or yoga.

Create time for stretching

Stretching regularly (even on a rest day) helps to optimise function at the joint. Below are a few stretches specific to reducing the risk of knee injury.

Lying Glute Stretch:

  • Lie on the floor face up, with knees and hips bent.

  • Place your left ankle across your right thigh.

  • Grasp your right thigh with both hands and pull it towards your chest gently.

  • Hold for 20-30 seconds, before repeating on the opposite leg.

Kneeling Hip Flexor Stretch:

  • Start off in a kneeling lunge positon, with one leg on the floor and the other bent 90 degrees in front of you.

  • Shift your body weight slightly forward while maintaining an upright positon.

  • Hold for 20-30 seconds and then slowly release. Then switch sides.

Heel Drop/ Calf Stretch:

  • Stand on the edge of a step or a block. Place the left foot on the ground, keeping the ball of the right foot on the step.

  • Slowly lower the right heel, so it drops below the step.

  • Hold for 20-30 seconds, before slowly lifting it back up.

  • Repeat several times before changing sides.


Try some strengthening exercises

The Clamshell:

  • Lie on one side propped up on your forearm, with your knees bent on top of each other and hips stacked.

  • Keeping your feet together, lift your top knee towards the ceiling (opening the clamshell). Make sure your core remains stable.

  • Lower leg back down and repeat.

  • Aim to do 3 x 10 of these per leg.

Single Leg Squat:

  • Stand with both feet pointing forward, hip width apart.

  • Raise the left leg off the floor and balance on your right foot.

  • Bend the right leg and slowly lower yourself down into a squat position. Make sure you keep your right knee centred over the ball of your foot.

  • Push back up slowly.

  • Try and aim for 3 sets of 6 repetitions per leg.

Side plank leg lift

  • Start on your side supporting yourself on your elbow, with the lower leg bent at the knee behind you.

  • Make sure hips are level and stacked.

  • With a straight top leg, raise it off the floor to a comfortable height without moving the rest of your body.

  • Then slowly drop the leg back down.

  • Try and aim for 3 sets of 6 repetitions per leg.

Invest in running shoes

Running shoes help absorb the shock every time your foot hits the ground. The duration that the shoes last is up for debate; however, they usually last between 300 to 450 miles[2][3]. After this they lose their cushioning and become less supportive, which could lead to injury.

It is also important that you wear running trainers that support your foot shape as well as your gait. Many sports shops offer a gait analysis test. This looks at the way the foot rolls (pronation and supination) while walking or running, to determine which shoe is best for you.

Observe your running style

Your running style can have a high impact on the knee. Follow these steps to protect your knees.

  • It is important to keep your knees soft and bent during the landing phase of your stride. A full extended leg can have a high impact on the knee joint.

  • Feet should be pointed in the direction of travel; if the foot is facing the side it can have a twisting effect on the knee and the ankle.

  • Avoid heel striking, which is when the heel contacts the ground first during a stride. Instead, try to land with your whole foot and under the knee. This reduces the impact load on the knee joint.

  • It is also important to look at your cadence (strides per minute). If your cadence rate is low, it can cause you to over-stride and heel-strike. Increase your cadence rate by taking shorter strides at a slower speed.

Have a break from the concrete

Running on hard surfaces means that the joints are suffering from a lot of repeated impact. It is important to change the terrain you’re running on. Rather than running on a pavement, if you can, try running in a field or off-road. If this isn’t possible treadmills or running tracks are a suitable alternative.


Where can I get further guidance?

If you’re suffering from knee pain or looking at ways to prevent knee pain, the team at Optimi are here to help. The Optimi app provides personalised exercise and rehabilitation programmes designed by world-class physicians. These are all accessible from your phone, so you can access your plan anytime, anywhere.

For reference, and further reading:

Nielsen RO, Buist I, Sørensen H, Lind M, Rasmussen S. Training errors and running related injuries: a systematic review. Int J Sports Phys Ther –

Rethnam, U., Makwana, N. Are old running shoes detrimental to your feet? A pedobarographic study. BMC Res Notes 4, 307 (2011) –

Wegener C, Burns J, Penkala S: Effect of neutral-cushioned running shoes on plantar pressure loading and comfort in athletes with cavus feet: a crossover randomized controlled trial. Am J Sports Med. 2008 –