Runner's Knee: Causes & Recovery Guide

Runner's knee (medically known as patellofemoral pain syndrome) is the most common running-related injury in Hong Kong. Whether you are training for the Standard Chartered Marathon or just jogging in your local park, knee pain can sideline you for weeks or months if not managed properly.

What Does Runner's Knee Feel Like?

The hallmark symptom is a dull, aching pain around or behind the kneecap (patella). It is often worse when going downhill, descending stairs, squatting, or sitting with bent knees for a long time. Some runners also feel a grinding or clicking sensation when bending the knee.

Common Causes

• Training errors — increasing mileage or intensity too quickly (the most common cause)
• Muscle weakness — weak glutes and quadriceps cause the kneecap to track improperly
• Poor running form — over-striding, heel striking, or excessive hip adduction
• Biomechanical issues — flat feet, tight IT bands, or tight calf muscles
• Inappropriate footwear — worn-out running shoes or shoes that don't suit your foot type

The 10% Rule

One of the simplest ways to prevent runner's knee is to follow the 10% rule: never increase your weekly mileage by more than 10%. If you ran 20 km this week, do no more than 22 km next week. Your body needs time to adapt to the load.

Recovery – 4 Key Exercises

1. Glute Bridge

Lie on your back with knees bent and feet flat on the floor. Squeeze your glutes and lift your hips toward the ceiling. Hold for 3 seconds at the top. Do 3 sets of 12. Strong glutes reduce the rotational stress on your knee.

2. Clamshell

Lie on your side with legs bent at a 45-degree angle. Keeping your feet touching, lift your top knee as high as you can without rotating your pelvis. Do 3 sets of 15 on each side. This targets the gluteus medius, a key stabiliser for runners.

3. Straight Leg Raise

Lie on your back with one leg straight and the other bent. Tighten your quadriceps on the straight leg and lift it to the height of the opposite knee. Lower slowly. Do 3 sets of 12 on each leg.

4. Wall Squat with Ball

Stand with your back against a wall and place a small ball (or foam roller) between your knees. Squat to a comfortable depth, keeping the ball squeezed. Hold for 10 seconds. Repeat 10 times. This activates the VMO muscle, which is critical for patellar tracking.

When to Return to Running

A good rule of thumb: you can start running again when you can walk briskly for 30 minutes without pain. Begin with a run-walk programme — run for 2 minutes, walk for 2 minutes, repeated 10 times. Gradually increase the running intervals over 2-3 weeks. If pain returns, drop back a level and continue strengthening.

Disclaimer: This article is for informational purposes. Consult a physiotherapist for a personalised assessment and treatment plan.