Knee Pain in Young Adults: Why Is It Increasing?

The load mismatch

Knees tolerate a lot, but they adapt slowly. When activity jumps faster than the tissues can adapt, pain follows. That's the common thread in most young adult knee pain.

The pattern often goes like this: a mostly sedentary work week, then a sudden commitment to running, a new gym programme, a trekking holiday or weekend football. The knee isn't damaged. It's overloaded.

The usual suspects

Patellofemoral pain. Pain around or behind the kneecap, worse on stairs, squatting or after sitting through a film. It's the most common cause of knee pain in young active people.

Patellar tendinopathy. Pain just below the kneecap, common in jumping sports and after increasing gym leg work.

Iliotibial band pain. Pain on the outside of the knee, typical in runners who increase mileage quickly.

Ligament and meniscus injuries. These usually follow a specific event: a twist, a landing or a tackle. Swelling within hours of an injury is a reason to be assessed promptly. Our ACL recovery guide explains how those are managed.

Why it seems more common

Two things are happening at once. Young people are more sedentary during the week, so they have less baseline strength. And more of them are taking up running, gym training and adventure sport as adults, often with ambitious plans and little progression. That combination produces overuse knee pain.

What actually helps

Rest alone doesn't fix it. The pain often settles, then returns as soon as training resumes, because nothing about the knee's capacity changed.

What works is reducing the aggravating load temporarily, then building strength progressively. For most young adult knee problems, that means quadriceps and hip strengthening. Wall squats, step ups, lunges and hip abduction work are common. For tendon pain, specific loading such as isometric holds can reduce pain early.

Then return to your sport gradually, with sensible weekly increases rather than jumping straight back to where you were. Our knee exercises section has step-by-step guides.

The role of hips and ankles

Knee pain doesn't always start at the knee. In many young adults, the hip muscles, especially those on the side and back of the hip, are weak. When they don't control the thigh well, the knee drifts inwards during running, jumping and stairs, loading the kneecap and tendons unevenly.

Stiff ankles can contribute too. When the ankle doesn't bend enough during squats or landing, the knee often compensates.

That's why a knee assessment looks above and below the knee. Strengthening the hips and improving ankle movement are often as important as working on the knee itself.

When to see a physiotherapist

If knee pain has lasted more than three or four weeks, stops you doing your sport, or followed an injury with swelling, get it assessed. The earlier the load gets adjusted and strength work starts, the quicker most young knees recover.