Seated Knee Extension

The seated knee extension strengthens the front of the thigh while you sit in an ordinary chair. It is easy to fit into the day, whether at the dining table, at work or while watching TV, which makes it a good everyday exercise for people with knee pain and arthritis.

Written by Dr. V. B. Rajendra Prasad, MPT, licensed in the US and UK.

1. Sit back in a chair with your feet flat
2. Straighten one knee fully, hold, then lower slowly

How to do it

  1. 1

    Sit back in a firm chair with your feet flat and your back supported.

  2. 2

    Tighten the thigh muscle of one leg and slowly straighten the knee until the leg is out straight. Pull your toes towards you.

  3. 3

    Hold for 3 to 5 seconds, feeling the muscle above the knee working.

  4. 4

    Lower the foot slowly back to the floor.

  5. 5

    Repeat, then change legs.

How many

10 repetitions on each leg, 2 to 3 sets, once or twice a day.

Common mistakes

Swinging the leg up. Lift slowly and stop if you feel a click with pain.

Not straightening fully. The last part of the straightening works the inner thigh muscle that supports the kneecap.

Leaning back or slouching. Sit tall with your back against the chair.

Make it easier

Straighten the knee only part of the way, or skip the hold to begin with.

Make it harder

Hold for longer, up to 10 seconds, or add an ankle weight of half a kilo to two kilos. A bag with a water bottle hung over the ankle works at home.

Who it helps

Knee osteoarthritis
Pain around the kneecap
Recovery after knee surgery (later stages)
Older adults with weak thighs
People who find exercises on the floor difficult

When to stop and check

If straightening against a weight causes pain under the kneecap, remove the weight and tell your physiotherapist. After ACL surgery, ask before doing this exercise with a weight, as some protocols limit it in the early months.

Not sure you are doing it right? A physiotherapist can watch you on a video call, correct your form and build a full programme around it.

Get my form checked

Frequently asked questions

Are seated knee extensions good for arthritis?
They are a useful part of a programme. Stronger thigh muscles take load off the knee joint. Most programmes combine them with standing exercises such as sit to stand.
Can I use ankle weights?
Yes, once you can do 3 sets of 10 easily without pain. Start light, around half a kilo, and increase slowly.

Related

Online physiotherapy: Knee Pain and OsteoarthritisOnline physiotherapy: Knee Replacement RehabilitationKnee Strengthening Exercises for Pain ReliefKnee Pain in Indian Women: Why It's So CommonKnee pain self-check

More knee exercises

Straight Leg RaiseHeel SlidesSit to StandAll exercises
Dr. Rajendra

Written by Dr. V. B. Rajendra Prasad, MPT. Licensed to practice in the US (NY state) and UK (HCPC).
20 years of clinical experience. About Dr. Rajendra