Quad Sets

Quad sets, also called static quadriceps or thigh tightening, wake up the big muscle at the front of the thigh without moving the knee. After knee surgery, or with a painful, swollen knee, this muscle quickly switches off and weakens. Quad sets are often the very first exercise given, even in a hospital bed, and they lead on to the straight leg raise.

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

1. Lie with a rolled towel under one knee, the leg relaxed
2. Tighten the thigh to press the knee down into the towel, and hold

How to do it

  1. 1

    Lie on your back on a bed or mat, or sit with your legs out straight. Place a small rolled towel under one knee.

  2. 2

    Pull your toes towards you.

  3. 3

    Tighten the muscle at the front of the thigh, pressing the back of the knee down into the towel. The kneecap should pull up slightly.

  4. 4

    Hold for 5 seconds, breathing normally.

  5. 5

    Relax the thigh fully, then repeat. Take the towel away when you finish.

How many

10 repetitions with a 5-second hold, 3 times a day. After surgery your physiotherapist may ask for more frequent short sessions.

Common mistakes

Holding your breath. Breathe out as you tighten.

Squeezing the buttocks instead of the thigh. Put a hand on the front of the thigh to feel the muscle harden.

Using a thick pillow. A small roll is enough, and a thick one keeps the knee bent.

Leaving the roll under the knee to rest. Resting with the knee bent over a pillow can make it harder to straighten the knee later.

Make it easier

Hold for only 2 to 3 seconds, or do the exercise without the towel, pressing the knee down into the bed.

Make it harder

Hold for 10 seconds, or put the rolled towel under the heel instead, so the knee has to straighten fully as you tighten. Once you can keep the thigh tight, move on to straight leg raises.

Who it helps

The first days after knee replacement or ACL surgery
Knee osteoarthritis
A painful or swollen knee
Older adults who are mostly in bed
Weak thighs after a fracture or plaster

When to stop and check

After knee surgery, follow your surgeon's and physiotherapist's advice, which may differ from this. Some protocols ask for the towel under the heel rather than the knee. If the thigh will not tighten at all, or the knee becomes hot and very swollen, or the calf becomes painful and swollen, contact your physiotherapist or doctor.

Not sure these are the right exercises for you? A physiotherapist can assess you on a video call and build a programme around your problem, guiding each exercise and correcting your form in live sessions.

Get a personal programme

Frequently asked questions

What are quad sets?
An exercise in which you tighten the thigh muscle (quadriceps) and hold it without moving the knee. Physiotherapists also call them static quads, isometric quads or thigh tightening.
Why is a rolled towel used under the knee?
It gives the knee something to press into, so you can feel the muscle working and know you are doing it right. The towel is only for the exercise. Do not rest with a pillow or roll under the knee.

Related

Online physiotherapy: Knee Replacement RehabilitationOnline physiotherapy: ACL Reconstruction RehabilitationWeek-by-Week Recovery After Knee ReplacementACL Reconstruction Recovery: A Week-by-Week GuideKnee pain self-check

More knee exercises

Straight Leg RaiseHeel SlidesSit to StandSeated Knee ExtensionAll 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