Knee strengthening exercises are one of the best ways to cure knee pain and stop it from coming back.
People who do knee strengthening exercises have less pain, recover quicker from injuries, function better and have less recurrences of pain.
Whenever there is weakness in the leg muscles, it means the knee joint is less well supported, resulting in more weight going through the bones and making knee problems much more likely. Knee strengthening exercises help to combat that1.
All the exercises here are easy to perform, quick, effective and suitable for most people, whether you are looking for knee strengthening exercises for runners, after an injury, with arthritis or almost any knee problem.
There are so many different knee strengthening exercises out there, it can be hard to know where to start. The best exercises to strengthen knees should include:
Pick and choose a couple from each group, opting for the knee strengthening exercises that you find challenging but not painful. Once they are too easy for you, move on to the Intermediate and Advanced knee strengthening exercise sections.
The quadriceps are the muscles at the front of the thigh that straighten the knee. Weak quads are one of the most common causes of knee pain making quads knee strengthening exercises an important part of any rehab programme. If you are looking for knee strengthening exercises after injury, these are a good place to start.
Purpose: Maintain and strengthen the Quads without moving the knee, enable full straightening of the knee. Ideal in the early stages following an injury or surgery.
Starting position: Lying flat on your back or sitting up. Leg and knee straight.
Action: Tighten the muscle on the front of the thigh by pushing your knee down. You should feel your thigh muscles clench. Hold for 3 secs.
Repetition: Repeat 10-20x every 3-4 hours.
Variations: If you are struggling to get your knee to straighten fully, place a rolled up towel underneath the ankle so that your leg is lifted slightly on the bed. Then do the exercise as described. Lifting the knee up slightly lets gravity help the knee to straighten.
Purpose: Strengthen the quads muscles without much knee movement. Helps improve strength and control.
Starting position: Lying flat on your back or sitting up with your leg horizontal on a flat surface such as a bed. Place a rolled up towel (approx 10cm diameter) under the knee.
Action: Pull your toes towards you and clench you thigh muscles. Slowly lift your foot up off the bed until your knee is straight (keep your knee resting on the towel). Hold for 3-5 secs and slowly lower.
Repetition: repeat 10-20 times, 3x daily.
Progression: 1) Increase the size of the towel under the knee 2) Add a weight e.g. by wearing a shoe, or using a light ankle weight. Progress further by using a heavier weight.
Purpose: Strengthen the Quads muscles without bending the knee. NB Do not do this if you have a history of back problems.
Starting position: Lying flat on your back. Leg and knee to be worked straight, other leg bent.
Action: Pull your toes towards you and tighten/clench the muscle on the front of the thigh, locking your knee straight. Lift your foot up about 6 inches off the bed. Hold for 3-5 secs and slowly lower. Ensure your knee stays straight the whole time.
Repetition: repeat 10-20 times, 2x daily.
Progression: Add a weight e.g. by wearing a shoe.
Purpose: Strengthen quads, increase knee mobility, great to do anytime sitting for prolonged periods (30mins+) to stop the knee getting stiff.
Starting position: Sitting on a firm chair with your knee bent and your foot on the floor.
Action: Lift your foot up and straighten your knee as much as possible. Hold for 3-5 secs and slowly lower.
Repetition: 5-20 times, 3x daily.
Progression: Strengthen further by adding an ankle weight.
Purpose: Increase quads strength without putting weight through the knee joint. Good in the early stages of recovery.
Starting Position: Sit in a chair with your feet on the floor.
Action: March your legs up and down one at a time. Lift your knee and foot up and then back down.
Repetition: Repeat for about 1 minute, 2x daily and any time you are sitting for more than 20 minutes to stop your knee getting stiff.
Progression: Add a weight.
The hamstrings are the muscles on the back of the thigh that bend the knee. You need a good combination of strength and length in these muscles. These hamstring strengthening exercises are particularly useful knee strengthening exercises for runners.
Purpose: Strengthen the hamstrings muscles without having to move the knee - perfect after a knee injury or surgery.
Starting Position: Sit in a chair with your heel against the leg of the chair and your feet firmly on the floor.
Action: Press your heel firmly backwards into the chair leg feeling the back of your thigh tightening/clenching. Hold for 3-5 secs.
Repetition: Do 10-20x, 2x daily.
Note: The foot shouldn’t move during this knee exercise.
Purpose: Strengthen hamstrings without any weight going through the knee joint, increase knee mobility (flexion), aid circulation.
Starting position: Lie on your tummy (on the floor or bed) with your legs straight.
Action: Lift your foot off the floor and bring it towards your bottom as far as you can. Slowly return to the starting position.
Repetition: Repeat 10-25x, 3x daily.
Notes: 1) You are aiming to get your heel all the way to your bottom 2) Make the exercise easier by hooking your good leg underneath the bad and using it to help lift the bad leg up.
Progression: Add a weight e.g. a shoe or ankle weight.
Purpose: Improve the strength of hamstrings and mobility of the knee.
Starting Position: Stand up straight holding on to something stable e.g. chair or table.
Action: Lift your foot up as far as you can towards your bottom, bending the knee. Hold for 3-5 secs.
Repetition: Do 5-25 times, 2x daily.
Progression: Add a weight e.g. shoe or ankle weight.
Note: 1) Don’t bend forwards - keep your body upright 2) keep your knees in line with each other- don’t let your thigh come forwards.
The glutes are the buttock muscles, and they play a vital role in ensuring the forces go through the knee evenly. The glutes are often forgotten about in knee strengthening exercises.
Virtually everyone who suffers from knee pain has weak glutes, so they are well worth doing. Indeed studies have shown that strengthening glute medius reduces pain and improves functional recovery following knee surgery2.
Purpose: Maintain and strengthen the Glutes without the knee moving - the perfect place to start.
Starting position: Lying down or sitting up.
Action: Clench your buttocks together as tightly as you can and hold for 3 seconds. You should feel yourself rise up from the chair slightly.
Repetition: Repeat 10-20x every 3-4 hours.
Variation: If you find this uncomfortable, try doing this knee exercise lying down, either with your legs out straight or your knees bent.
Purpose: Strengthen the glutes to help support the knee and prevent excessive weight going through the inner side of the knee – a must for anyone with knee pain!
Starting position: Lie on your side with your hip and knees bent approx 90°, feet together.
Action: Keeping your feet together, lift the top knee up as high as you can. Hold for 3 seconds and slowly lower.
Repetition: Repeat 10-25x on each side, 2x daily.
Note: Do not let your top hip roll backwards.
Progression: Squeeze your heels together while doing the exercise to work the glutes harder.
The calf muscles can be found on the back of the leg between the knee and the ankle. They move the foot and ankle, and help support the knee so should always been included with knee strengthening exercises.
Purpose: Strengthen the calf muscles to help support the knee, helps with walking and running.
Starting position: Stand with your feet slightly apart,
weight equally distributed, holding onto something solid for balance if needed such as a chair or the wall.
Action: Rise up onto your toes lifting your heels as high as possible. Keep your body upright as you do this, don’t bend forwards. Hold for 3-5 secs and slowly lower.
Repetition: Repeat 10-30 times, 2x daily.
Top Tips: Try and push up equally through each leg.
Here you will find knee strengthening exercises that work two or three muscle groups at the same time - it's like buy one get one (or two) free!
Purpose: Improve knee mobility, strengthen quads and glutes, improve general fitness.
Starting position: Sit in a firm chair, feet on the floor.
Action: Lean forwards, lift your bottom and stand up straight and then sit back down.
Repetition: Repeat 10-30x.
Notes: 1) You can make this exercise easier by pushing up through your arms too 2) The higher the chair, the easier the exercise.
Progression: 1) Don’t use your arms 2) Use a lower chair 3) Increase the speed you do knee strengthening exercises at 4) Hold a heavy weight – e.g. bag of books during this knee exercise.
Purpose: Excellent knee strengthening exercises for the hamstrings, quads and buttock muscles.
Starting Position: Lie on your back with both knees bent about 90° and your feet on the floor/bed.
Action: Clench your buttocks and lift your bottom off the bed as high as you can without arching your back. Hold for 3-5 seconds and slowly lower
Repetitions: Repeat 10-25 times, 1-2x daily.
Note: 1) Keep your back straight – don’t let it arch as you lift up, it should be your bottom doing the work 2) Don’t hold your breath – keep breathing normally.
Balance / proprioception is really important to prevent knee injuries. A quick way to tell whether you should be doing balance exercises as part of your knee strengthening exercises programme is to try standing on one leg with your eyes closed.
If you can’t do it for one minute, you should do some balance exercises. This exercise helps your body learn the subtle adjustments needed for good balance.
Starting position: Standing near a wall or chair for support.
Action: Lift up your good leg and stand on one leg for as long as you can. It is normal to wobble a bit.
Repetition: Spend 5 minutes doing this 2x daily e.g. when brushing your teeth.
Progression: 1) Close your eyes and perform the exercise as above - you'll be surprised how much harder it is
2) Try Stage 2.
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As your muscles get stronger, you will be able to increase the number of repetitions of each of these knee strengthening exercises.
You will probably need to do knee strengthening exercises at least four times a week for about a month before you notice much change in your knee pain at which point you may also want to add in some knee stretches -it's important to have enough strength before you start stretching else you can make things wors).
Remember, you should always check with your doctor before starting a new exercise programme, particularly if you have injured your knee, to ensure these knee strengthening exercises are safe to do.
Page Last Updated: February 25, 2020
Next Review Due: February 25, 2022
1. Deconditioned Knee: The Effectiveness of a Rehabilitation Program that Restores Normal Knee Motion to Improve Symptoms and Function: K. Shelbourne, A. Biggs & T. Gray. North American Journal of Sports Physical Therapy, May 2007
2. The effect of gluteus medius strengthening on the knee joint function score and pain in meniscal surgery patients: Eun-Kyung Kim, PT, PhD. Journal of Physical Therapy Science, October 2016