Overview

The terminal knee extension targets the last part of straightening the knee — the range where the quadriceps often need the most work after injury, surgery or long periods of sitting. It is a simple, low-load exercise that can be done almost anywhere.

Primary Purpose

Strengthen the quadriceps, especially at the end range of straightening
Improve the control and strength needed for walking and stairs
Rebuild quadriceps activation early in rehabilitation

Equipment Required

A chair or bench
A rolled towel or small cushion
Optional: a resistance band or ankle weight

Step-by-Step Instructions

Sit on a chair with your knee bent and a rolled towel under the knee, so the heel is slightly off the floor.
Press the back of the knee down into the towel while straightening the leg.
Squeeze the thigh muscle at the top, hold for 3–5 seconds, then lower slowly.
Repeat 10–15 times, then rest.
To add resistance, loop a band around the back of the knee and anchor it, or add a light ankle weight.

What You Should Feel

Work in the front of the thigh, especially just above the kneecap. It should feel like effort, not pain. Stop if the knee catches, swells or hurts sharply.

Common Mistakes

Lifting the thigh off the chair instead of straightening the knee
Bouncing at the end of the movement
Holding the breath — breathe normally
Using a band so heavy that form collapses

Easier Alternatives

Straighten the knee without resistance first
Do fewer repetitions with a longer hold
Support the thigh with the hands

Progressions

Increase the hold time
Add a light ankle weight or band
Progress to standing terminal knee extensions with a band behind the knee

Who Should Avoid This

Do not use this as self-directed rehabilitation after recent knee surgery, a suspected fracture or a major injury without clearance. A locked knee, rapid swelling or inability to straighten the knee needs assessment first.

References

Willy RW, et al. "Patellofemoral Pain: Clinical Practice Guidelines." Journal of Orthopaedic & Sports Physical Therapy. 2019;49(9):CPG1-CPG95. https://doi.org/10.2519/jospt.2019.0302
Neal BS, et al. "Best practice guide for patellofemoral pain." British Journal of Sports Medicine. 2024;58(24):1486-1495. https://bjsm.bmj.com/content/58/24/1486

This information is for education only and is not a medical diagnosis. InjuryAtlas does not replace an assessment by a qualified health professional. If you have severe pain, visible deformity, numbness, loss of function, or symptoms that are getting worse, seek medical care promptly.

Terminal Knee Extension