Knee Pain When Cycling: Causes and How to Fix It
Knee pain is one of the most common complaints in cycling, and the good news is that it is usually a bike-setup problem rather than an injury. Where the pain sits tells you a lot: pain at the front of the knee, the back, or the sides each points to a different cause. This guide explains what each location means and how your saddle and cleat position drive it.
Where the knee hurts identifies the cause: pain at the front usually means the saddle is too low or too far forward, pain at the back means it is too high or too far back, and pain at the sides points to cleat position rather than the saddle.
Rather than guessing, measure your actual position with your own camera.
Measure my knee angle€5 for one fit, or 10 fits for €25. See pricing →
Where the pain is tells you the cause
Cycling knee pain rarely comes out of nowhere. Because your legs repeat almost the same movement thousands of times an hour, a small position error becomes a repetitive strain. The location of the pain is the first clue.
Pain at the front of the knee (around or below the kneecap)
This is the most common pattern, and it usually points to a saddle that is too low or set too far forward. Both increase how much your knee bends at the top of the pedal stroke, which raises pressure behind the kneecap. Long climbs, big gears and a low cadence make it worse.
- Most likely fixes: raise the saddle in small steps (a few millimetres at a time), and check that the saddle is not pushed too far forward.
- Also check: pedalling in too high a gear at low cadence loads the knee; spinning a lighter gear often helps.
Pain at the back of the knee
This usually points the other way: a saddle that is too high or too far back. Your leg over-extends at the bottom of the stroke, stretching the hamstring tendon and the back of the knee. You may also notice your hips rocking in the saddle.
- Most likely fixes: lower the saddle slightly, and check it is not slid too far back on the rails.
Pain on the inside or outside of the knee
Side pain usually points to cleat position (on clipless pedals) rather than saddle height. Cleats angled wrong, or a stance width that does not match your hips, make the knee track sideways instead of straight up and down.
- Most likely fixes: check cleat angle and fore-aft position; small changes have a big effect. If one knee hurts and the other does not, cleats are the first suspect.
Wondering where your own position sits? You can measure it in twelve seconds.
Measure my knee angle →The measurement that ties it together
Front and back knee pain both come back to one number: knee extension angle at the bottom of the pedal stroke. Professional fitters aim for roughly 138–145 degrees for endurance road riding and 140–148 degrees in a racing position (135–143 for comfort). Too little extension (a bent leg) means the saddle is low; too much (an over-straight leg) means it is high.
You cannot judge this angle by eye while pedalling, which is exactly why it goes wrong. Measuring it from a short video removes the guesswork and tells you which direction to move.
When it is not the bike
Most cycling knee pain is position-related, but not all of it. If pain is sharp, sudden, involves swelling, or persists after you have corrected your setup, stop guessing and see a physiotherapist or sports doctor. A bike fit fixes bike problems; it does not diagnose an injury.
FAQ
Why does the front of my knee hurt when cycling?
Most often because the saddle is too low or too far forward, which over-bends the knee at the top of the pedal stroke and raises pressure behind the kneecap. Raising the saddle in small steps and using a lighter gear usually helps.
Can a saddle that is too high cause knee pain?
Yes, typically pain at the back of the knee, because the leg over-extends at the bottom of the stroke. Rocking hips in the saddle is another sign the saddle is too high.
Should I stop cycling if my knee hurts?
Ease off and correct your setup first. If the pain is sharp, swollen, or continues after you have adjusted your position, see a physiotherapist or sports doctor rather than pushing through it.
References
- Bini R, Hume PA, Croft JL (2011). Effects of bicycle saddle height on knee injury risk and cycling performance. Sports Medicine, 41(6):463–476. doi:10.2165/11588740-000000000-00000
- Bini RR, Flores Bini A (2018). Potential factors associated with knee pain in cyclists: a systematic review. Open Access Journal of Sports Medicine, 9:99–106. doi:10.2147/OAJSM.S136653
- Johnston TE, Baskins TA, Koppel RV, Oliver SA, Stieber DJ, Hoglund LT (2017). The influence of extrinsic factors on knee biomechanics during cycling: a systematic review of the literature. International Journal of Sports Physical Therapy, 12(7):1023–1033. doi:10.26603/ijspt20171023
- Clarsen B, Krosshaug T, Bahr R (2010). Overuse injuries in professional road cyclists. American Journal of Sports Medicine, 38(12):2494–2501. doi:10.1177/0363546510376816
General position guidance, not medical advice. Individual anatomy varies; consult a physician or professional fitter for persistent pain. How BikeFit/LAB measures, and where its reference ranges come from · How accurate is an AI bike fit?
Rather than guessing, measure your actual position with your own camera.
Measure my knee angle€5 for one fit, or 10 fits for €25. See pricing →