Why Your Knee Hurts When You Run: Common Running Injuries and How PT Fixes Them

Knee pain when you run is usually a load problem, not a sign that your knee is damaged. The most common causes are runner's knee, IT band syndrome, and patellar tendinopathy, and they typically show up when training volume, strength, or mechanics get out of balance, not because the joint is wearing out. The good news: with the right plan, most runners fix the root cause and keep running while they do it.

The Short Answer: Your Knee Is Usually the Victim, Not the Cause

Your knee sits between your hip and your foot, so it absorbs whatever those two are not handling well. When you add miles faster than your body adapts, change shoes or surfaces, or run with a weak link upstream, the knee is often where the stress shows up first.

That is why the pain rarely resolves with rest alone. Rest calms the symptom, but the moment you ramp back up, the same load lands on the same spot. Fixing it means finding what is driving the overload and changing it, which is exactly what a running-focused physical therapy plan for runners is built to do.

The Most Common Running Knee Injuries

Most running knee pain falls into a few recognizable patterns. Here is how to tell them apart.

Runner's knee (patellofemoral pain). A dull ache around or behind the kneecap, often worse going downhill, down stairs, or after sitting for a while. It usually builds gradually rather than starting with one sharp moment. It is the most common running knee complaint.

IT band syndrome. Sharp or burning pain on the outside of the knee, often arriving at a predictable point in a run and easing when you stop. It tends to flare with downhill running and higher mileage.

Patellar tendinopathy (jumper's knee). Pain right below the kneecap, on the tendon itself, that is tender to press. It often responds to load in a telling way: it can warm up early in a run and then worsen afterward.

What to rule out. Not all knee pain is a simple overuse pattern. Pain with swelling, catching or locking, or a sense that the knee might give way can point to a meniscus or ligament issue and deserves a hands-on assessment from a knee pain PT. Pain that actually originates at the hip can also refer down to the knee, which is one reason a full-body evaluation matters.

What Is Actually Causing It (It Is Usually Not Your Knee)

When a runner comes in with knee pain, the knee is where it hurts, but the cause is often somewhere else. The usual suspects:

Training load that outpaced your body. A jump in mileage, a new speed block, more hills, or stacking hard days too close together. This is the single most common thread behind running injuries, and it is also the most preventable once you know how to manage it.

Hip and glute weakness. When the muscles that control your hip and pelvis cannot keep your leg tracking well, the knee takes the slack. Hip and gluteal strength deficits are among the most consistently identified contributors to patellofemoral pain in the research literature.

Mechanics and cadence. How you load, how far your foot lands ahead of you, and your step rate all change how much stress reaches the knee. Small changes here can meaningfully offload an irritated structure.

Footwear and surface changes. New shoes, worn-out shoes, or a sudden shift to more road or more downhill can be enough to tip a borderline knee into pain.

The point is simple: chasing the pain at the knee alone tends to fail, because the knee is rarely working alone. Once the pain settles, the same weak links are also what a good injury prevention program targets to keep it from coming back.

How Physical Therapy Fixes Running Knee Pain

Good running PT is not heat, a few stretches, and "stop running for six weeks." It is a process of finding the real driver and rebuilding capacity so the knee can handle your training again.

It starts with a real assessment. A running-focused evaluation looks at strength, joint mechanics, and how you move through your whole lower body, not just the sore spot. At Grit, that includes running gait analysis and force plate testing, so the plan is built on what your body is actually doing rather than a guess.

It treats the cause, then rebuilds load. Once the driver is clear, the work is targeted: strengthen the weak links, adjust the mechanics that matter, and progressively reload the tissue so it can tolerate your mileage. The aim is a knee that holds up at full training, not one that only feels fine at rest.

You usually keep running. A well-built plan modifies your training rather than stopping it. At Grit, most runners keep running in some form throughout their program, with load managed around their schedule and goals. Stopping completely is reserved for the cases where it is truly necessary.

It is built around the runner. Every runner's program should reflect their gait, training load, and goals rather than a generic protocol. Grit's model is one-on-one with a Doctor of Physical Therapy for the full session, which is what makes that level of individualization possible.

When to See a Physical Therapist, and When It Might Be Serious

A good rule: if knee pain has changed how you run for more than a week or two, or it comes back every time you build mileage, it is worth getting assessed rather than guessing.

Get it looked at sooner if you notice any of these:

• Swelling that does not settle
• Catching, locking, or the knee giving way
• Pain that worsens run over run despite backing off
• Pain that started with a single sharp or twisting moment

In Virginia you can see a physical therapist directly, without a physician's referral, so there is no gatekeeping step between you and an evaluation.

Running PT at Grit in Richmond

Grit Physical Therapy and Performance works with Richmond runners at every level, from first-timers building toward a 5K to marathoners chasing a PR along Monument Avenue. Care is one-on-one with a DPT every session, includes running gait analysis and force plate testing, and is built around how you actually train. Grit serves runners across Richmond, Henrico, Midlothian, Tuckahoe, and the West End, and works out-of-network with a flat per-session rate and a superbill you can submit for potential reimbursement.

If knee pain keeps interrupting your training, schedule a free discovery call and get started with running PT built around your goals.

Frequently Asked Questions

Can I keep running with runner's knee?

‍Often, yes, with the load adjusted. Many runners can keep running in a modified form while the underlying cause is addressed, rather than stopping cold. The right amount depends on your symptoms and what the assessment finds, which is why an individualized plan beats a blanket rule.

How do I tell IT band pain from a meniscus problem?

‍IT band syndrome usually shows up as pain on the outside of the knee that arrives at a predictable point in a run and eases with rest, without swelling. Meniscus issues more often involve swelling, catching or locking, or pain with twisting and deep bending. If you have those signs, get a hands-on assessment rather than self-treating.

Did new shoes or more mileage cause my knee pain?

‍They are two of the most common triggers. A jump in mileage or intensity, or a sudden change in shoes or running surface, can overload a structure faster than your body adapts. Mapping your pain to recent training changes is one of the first things a PT will do.

Is it bad to run through knee pain?

‍Mild, stable discomfort that does not worsen during or after a run is often workable with guidance. Pain that climbs run over run, changes your stride, or comes with swelling or instability is a signal to stop pushing and get assessed. Running through that kind of pain tends to deepen the problem.