Sore knees when you walk or run? A physical therapist explains when you should stop, when you can continue and how to avoid further discomfort
Keep your knees safe with this expert guidance
Ever feel your knees giving you grief when you embark on a long walk or run?
That's exactly what happened to me a few minutes into a gentle-paced run last weekend.
Normally, I’d have called it quits or slowed down my pace, but I'm currently halfway through a four-month marathon training block and I can't afford to drop any mileage.
An hour later, with the patellar tendons below my kneecaps feeling a little sore, I resolved to ask an expert what I could have done differently.
“The honest clinical answer is that pain during running exists on a spectrum, and the right decision depends on the type, location and behavior of the pain," says Dr Andrew Gorecki of Superior Physical Therapy, a practicing physical therapist who specializes in treating people with chronic pain.
In other words: what hurt for me might not hurt for you.
It’s important to seek a professional diagnosis and help for any persistent running or walking pain, but Gorecki has a framework he uses with all his patients to help them identify when they should stop a session and when they can keep going.
Here's how it works.
How to know if you should stop the workout
Gorecki says you should stop your walk or run immediately if the pain is “sharp, stabbing or feels like something is pinching inside the joint”.
That's different from a dull ache and usually means the tissue is irritated.
“Stop if the pain gets progressively worse as you run,” he says.
“If mile one is a three out of 10, mile two is a five out of 10, mile three is a seven out of 10, stop. Continuing turns a manageable issue into a bigger one.”
You should also pack it in if the pain changes your walking or running form.
“If you start compensating—limping, favoring one leg, shortening your stride—your body is telling you something is wrong. Compensation causes new injuries,” he says.
The same is true if the pain radiates.
“Knee pain that spreads down the shin, up into the thigh, or wraps around the joint is a signal to stop and evaluate.”
If you feel a pop, snap or catch you should also pump the brakes.
“That's a mechanical warning sign. Don't try to run through it.”
If you notice any swelling or visible change in the knee, walk home—gently. Or call someone to pick you up.
How to know if you can continue with your workout
Fortunately none of those issues occurred during my 11-mile run and I felt fit enough to pick up my training the following day.
Mostly what I felt was a dull ache that wouldn't budge.
If pain stays constant at a low level like this, such as a two or three out of 10, and doesn't get worse, you can generally carry on, Gorecki tells Fit&Well.
Likewise, you can probably keep going if the following applies:
- a dull ache that warms up and fades after the first mile;
- you're able to maintain normal running form without compensating;
- the pain fully resolves within an hour of finishing the run.
“The rule of thumb I give patients is that if the pain is worse tomorrow than it was during the run, that’s the warning sign. Run smart today, evaluate honestly tomorrow,” adds Gorecki.
What you can do to adjust the session
If you do decide to carry on, Gorecki recommended making some modifications to your session.
Here are his suggestions, in order of impact.
1. Slow down
Reduce your pace by 15-20%.
“Faster running loads the knee much more than slower running, and speed is often the variable that pushed you past the threshold in the first place,” he says.
Just slowing down often eliminates the pain without any other changes.
2. Shorten your stride
“Overstriding is one of the biggest contributors to knee pain in runners at any level,” says Gorecki.
“When your foot lands too far in front of your body, the knee absorbs a much bigger impact than it should.”
Shortening your stride by 10% and letting your foot land more directly under your body reduces peak knee load significantly.
Cadence (steps per minute) increases naturally when the stride shortens, and that’s a good thing, he adds.
3. Adjust your foot strike
If you’re a heavy heel striker landing hard on your heel with a fully extended knee, transitioning to a slightly more midfoot strike can help.
“However, altering foot strike is a change to make gradually over weeks, not mid-run,” cautions Gorecki.
“Sudden foot strike changes create new injuries. If you’re already midfoot striking, don’t change anything.”
4. Change terrain
Running, hiking or even walking downhill can dramatically increase knee load.
“If your knee is bothering you, switch to a flat route or turn around before the downhill portion,” suggests Gorecki.
“Downhill sections can turn manageable knee pain into significant injury.”
5. Shift gears
An overzealous volume or intensity is often the primary culprit of knee pain.
“For relative beginners, it’s usually volume,” says Gorecki. “You’re doing too much too fast.”
Taking walking breaks throughout your run and reducing weekly mileage by 30-50% for two weeks usually resolves most beginner knee complaints, he says.
For more advanced hikers or runners, the issue is more often intensity or form drift late in a training block.
“Reduce the intensity or speed of your quality sessions and add in extra recovery days.”
Dr Andrew Gorecki, PT, DPT, FAFS, is a practicing physical therapist and owner of Superior Physical Therapy in Traverse City, Michigan, where he has specialized in chronic spine, hip, shoulder and knee pain since 2011. In 2018 he co-founded MovementRx, a remote therapeutic monitoring (RTM) platform now used by physical therapy clinics across the US to deliver custom home exercise programs and track patient adherence, through which he has helped to treat over 25,000 patients.
