Runner’s Knee: Pain Under the Kneecap, Stretches and Exercises

01What

What is runner’s knee?

Runner’s knee is the common name for patellofemoral pain syndrome. The kneecap sits in a groove at the end of the thigh bone and glides up and down as the knee bends and straightens. When the load on this joint exceeds what the tissues can tolerate, pain develops around or under the kneecap. The term is sometimes used loosely for other running-related knee problems, such as iliotibial band syndrome on the outside of the knee or patellar tendinopathy below the kneecap.

02Symptoms

Symptoms

• A dull ache around, behind or under the kneecap.
• Pain when running, particularly downhill.
• Pain going up or, especially, down stairs.
• Pain when squatting, lunging, kneeling or jumping.
• Pain after sitting with bent knees for a long time, sometimes called the “cinema sign”.
• Clicking or grinding sensations, usually without pain significance.
• Usually no major swelling.

03Causes

Causes and risk factors

• Increasing running distance, speed or hills too quickly.
• Weakness of the quadriceps and hip muscles, especially the gluteals.
• Knee falling inward during running or squatting.
• Reduced flexibility of the quadriceps, hamstrings or calves.
• Foot posture, such as excessive pronation, in some people.
• Growth spurts in teenagers.
• Being female, as patellofemoral pain is more common in women.

04Evidence

What the evidence recommends

Two international consensus statements from patellofemoral pain research retreats reviewed treatments. Exercise therapy is recommended to reduce pain and improve function in the short, medium and long term, and combining hip and knee exercises is recommended over knee exercises alone. Foot orthoses and patellar taping can help in the short term. Combined interventions, such as exercise with orthoses or taping, may also be useful. Knee or lumbar manipulation alone and electrophysical treatments such as ultrasound are not recommended.

05Stretches

Stretches for runner’s knee

• Standing quadriceps stretch: hold the ankle behind you, knees together, 30 seconds each side.
• Hamstring stretch: heel on a low step, lean forward with a straight back, 30 seconds.
• Calf stretch: against a wall, 30 seconds with the knee straight and 30 seconds bent.
• Hip flexor stretch: half-kneeling lunge, 30 seconds each side.
• Foam rolling the quadriceps and outer thigh for 1–2 minutes, if comfortable.
• Stretching supports, but does not replace, strengthening.

06Exercises

Strengthening exercises

• Side-lying leg raises for the outer hip, 3 sets of 15.
• Clamshells with a band, 3 sets of 15.
• Glute bridges, progressing to single-leg bridges, 3 sets of 12.
• Straight leg raises for the quadriceps, 3 sets of 15.
• Wall sits at a comfortable depth, 30–45 seconds, 3 times.
• Step-ups onto a low step, keeping the knee in line with the toes, 3 sets of 10.
• Partial squats to a pain-free depth, 3 sets of 12.
• Single-leg balance with the knee slightly bent, 30 seconds.
• Mild discomfort up to about 3 out of 10 is generally acceptable if it settles within 24 hours.

07Running

Changing your running

• Reduce weekly distance and avoid downhill running for a few weeks.
• Run on flat, softer surfaces where possible.
• Increase step rate slightly (shorter, quicker steps), which reduces load on the knee.
• Build distance gradually, by around 10% a week.
• Cross-train with swimming or cycling with the saddle set high enough.
• Check that your shoes are not worn out.

08Taping

Taping, braces and insoles

Patellar taping can reduce pain in the short term, helping people exercise and stay active while strength improves. Knee sleeves and braces are often used for comfort, though evidence for them is limited. Prefabricated foot orthoses may reduce pain in the short term, particularly in people with more pronated feet. Ideas for taping are in our guide to KT tape for the knee.

09Recovery

How long does recovery take?

Many people improve within six to twelve weeks of consistent exercise and load management, though some have symptoms that come and go for longer. Returning to running is usually guided by symptoms: start with short, easy runs on flat ground when you can squat, hop and climb stairs comfortably, and build up gradually. Pain below the kneecap, rather than around it, may be a different condition; see patellar tendonitis.

10Cases

Three common situations

• New runner training for a first half marathon: reduce distance, add hip and knee strengthening, then rebuild gradually.
• Teenager with knee pain on stairs during a growth spurt: modify sport load, strengthen and reassure.
• Office worker with pain after sitting through meetings: straighten the legs regularly and start a strengthening routine.

11Summary

Key points to remember

• Runner’s knee causes pain around or behind the kneecap.
• It is usually caused by overload rather than damage.
• Combined hip and knee strengthening is the most effective treatment.
• Taping and insoles can help in the short term.