Is running bad for your knees?

For most people, running that builds up gently is not something to fear. Plenty of people run happily for decades. Knee trouble in beginners usually comes from doing too much too quickly, not from running itself. If you already have a knee condition, ask your doctor first.

Should I wear a knee brace or support when I run?

A support can feel reassuring, but it won’t fix the reason your knee hurts. If you feel you need one to get through a run, that’s a sign to rest and ask a doctor or physiotherapist what’s going on.

Is a treadmill easier on the knees?

Some people find a treadmill feels a bit softer and more even than pavement, and it has no downhill sections. It can be a useful way to come back after a break. Build up just as slowly as you would outside.

Can I keep walking if my knee hurts when I run?

If walking is completely pain-free, it’s usually fine to keep walking while you rest from running. If walking, stairs or getting up from a chair hurts, stop and see a doctor or physiotherapist.

Knee pain from running: what beginners should do

Mild, achy knees after your first weeks of running usually mean you’ve done a bit more than your legs were ready for, not that running is bad for you. Take a few days off running, then come back with shorter, slower runs, more walking breaks and flatter routes. If the pain is sharp, the knee swells, locks or gives way, hurts on stairs or when walking, or lasts more than a few days, stop running and see a doctor or physiotherapist.

Is it normal for knees to hurt when you start running?

A little stiffness or a dull ache around the knees in the first weeks is common, but real pain is not something to ignore. Your heart and lungs get fitter quickly; your muscles, joints and tendons take longer. When you add runs or speed faster than they can adapt, the knees are one of the first places to complain.

The key difference is between “my legs feel worked” and “something hurts”. The first is part of getting fitter. The second is a signal to back off.

How do I know if my knee pain is serious?

You can’t diagnose yourself from a list, but how the pain behaves tells you what to do next. Use this as a rough guide, and when in doubt, get it checked:

What you notice	What to do
A dull ache after a run that’s gone by the next day	Take an extra rest day and keep the next run easy
A mild ache that comes on during runs and fades afterwards	Shorten your runs, slow down, add walking breaks
An ache that’s still there after a few days of rest	See a doctor or physiotherapist
Sharp or stabbing pain	Stop running and get it checked
Swelling, warmth or redness	Stop running and get it checked
The knee locks, clicks painfully or gives way	Stop running and get it checked
Pain on stairs, when walking or at night	Stop running and get it checked

This guide isn’t medical advice. A doctor or physiotherapist can examine your knee and tell you what’s going on and how to fix it.

Why do beginners get knee pain from running?

Beginners usually get knee pain from building up too fast or running in a way that adds extra strain. The most common reasons are:

Doing too much, too soon. More runs, longer runs or faster runs before your legs are ready.
Running every session hard. No easy days for your legs to recover.
Long strides. Landing with your foot far in front of your body, knee straight.
Lots of downhill running. Going downhill puts more load on the front of the knee.
Worn-out or poorly fitting shoes. Less cushioning and support.
Weak hips and thighs. Muscles that tire quickly let the knee wobble more with each step.

What should you do when your knee hurts after a run?

When your knee hurts after a run, rest it from running and let it settle before you try again. A simple approach:

Stop running for a few days. Normal walking is fine if it’s completely pain-free.
Keep moving gently. Cycling or swimming can be good if they don’t hurt.
Soothe it if you like. A cold pack wrapped in a towel for 10 to 15 minutes can feel good.
Check before you restart. Walking, stairs and a gentle squat should all feel normal.
Restart easier than before. Shorter runs, slower pace, more walking breaks.
Watch the next day. If the ache comes back, rest again and get it checked.

If it doesn’t feel better within a few days, don’t keep testing it with runs. See a professional.

How can you run with less strain on your knees?

You can reduce strain on your knees by taking shorter steps, landing softly and keeping your runs easy. Small changes add up:

Shorter, quicker steps. Try to land with your foot roughly under your body instead of reaching out in front. Our guide to running cadence for beginners explains this in plain terms.
Run quietly. If you can hear your feet slapping, try to land more softly.
Choose flat routes for now. Save steep downhills for later, or walk them.
Slow down. An easy pace where you can still talk is gentler on everything.
Check your shoes. Running shoes that fit and still have their cushioning help. See our guide to running shoes for beginners.
Rest between runs. At least one day off between runs while you’re new. Our guide to rest days for runners explains why.

Can simple strength exercises help?

Yes, a few simple strength exercises twice a week can help your legs handle running better. You don’t need a gym. Stop any exercise that hurts your knee.

Sit-to-stand: stand up from a chair and sit back down slowly, 10 times.
Bridges: lie on your back, knees bent, and lift your hips off the floor, 10 times.
Calf raises: rise onto your toes and lower slowly, 15 times.
Step-ups: step up onto a low, sturdy step and back down, 10 times each leg.
Side-lying leg lifts: lie on your side and lift your top leg, 10 times each side.

If you already have knee pain, ask a physiotherapist which exercises suit you. They can give you a routine that fits your knee.

How do you build up again without hurting your knees?

Build up slowly, with walking breaks and at least a day of rest between runs. A gradual plan is the best protection there is. Run’s 5K plan starts with one minute of running and two of walking, and only adds more running when the last level felt manageable.

The Run app also listens to your knees, in a way. You rate any pain from 1 to 10 at the end of each week, and a score of 6 or more makes the next week easier. If you’ve had an injury before, or you’re over 50, the plan starts you one level lower. If that’s you, our guide to starting running after 40 has more tips.

The short version

Knees that feel a bit worked are part of getting started. Knees that hurt are telling you to slow down. Rest, come back gently, take shorter steps, and see a doctor or physiotherapist if the pain is sharp, swollen, or still there after a few days. Most beginners who listen early are back running comfortably in a short time.