Runner's Knee: Causes, Fixes & When to See a Physio

Runner's knee is one of the most common injuries we treat at our Londonderry clinic — and one of the most misunderstood. Runners often fear the worst when the front of the knee starts aching, but the reality is reassuring: it's usually an overload problem that responds very well to the right rehab.

What is runner's knee?

"Runner's knee" is the everyday name for patellofemoral pain syndrome — pain around or behind the kneecap where it meets the thigh bone. It typically shows up during or after running, and is often worse going downhill, on stairs, squatting, or after sitting still for a long time (the classic "cinema sign").

Crucially, it's a pain of overload, not structural damage. The load going through the kneecap joint has simply outpaced what the joint is currently prepared to handle. That's why the answer is rarely rest and scans — it's building the knee's capacity back up.

What causes it?

It's almost always a mismatch between load and capacity. Common triggers we see in Co. Derry runners include:

• Doing too much, too soon — a sudden jump in distance, pace or hills
• Weak hips and glutes — letting the knee drift inwards as you land
• Weak quads — less shock absorption through the kneecap
• A big change in surface or footwear
• Not enough recovery between hard sessions

Notice that most of these are modifiable — which is exactly why the outlook is good.

How do I fix runner's knee?

The evidence points clearly to load management plus strengthening, not rest alone. A typical plan looks like this:

1. Settle it down (don't stop completely)

Temporarily reduce the things that flare it — usually distance, hills and speed — to a level that keeps pain low. Complete rest deconditions the knee and often makes the return harder. Keep moving within comfort.

2. Strengthen the hips, glutes and quads

This is the part that actually fixes it. Progressive strengthening builds the capacity to absorb running load. Reliable starting exercises include:

• Spanish squats or wall sits for the quads
• Side-lying leg raises and banded walks for the glutes
• Step-downs to train control as the knee bends under load

3. Rebuild running gradually

Once pain is controlled and strength is improving, increase your running slowly — small, steady steps up in distance and intensity, with recovery built in. A physiotherapist can set the right numbers so you progress without flaring it.

Should I keep running?

Often, yes — many runners can keep running at a reduced level while they rehab, as long as pain stays low, settles within a day, and isn't trending worse. Running through sharp or worsening pain, though, tends to prolong the problem. When in doubt, get it looked at rather than pushing through.

When should you see a physiotherapist?

Book an assessment if your knee pain:

• Lasts more than two to three weeks or keeps returning
• Is stopping you running or training
• Isn't improving despite backing off

Seek prompt care if the knee locks, gives way, swells noticeably, or you can't weight-bear — these can signal something beyond simple overload.

At Oakleaf Physio in Londonderry we treat runners across Co. Derry every week. You can book directly, no GP referral needed, and we'll build a return-to-running plan around your goals. See more on the treatments we offer, including sports massage and shockwave for stubborn cases.

This article is general information, not individual medical advice. Knee pain has several causes — please see a qualified physiotherapist or your GP for an assessment tailored to you.