Reviewed by Dr. Bharath Loganathan, MS Ortho, MRCS (Edinburgh), DNB Orthopaedics Bharath Orthopaedics, Chennai Last reviewed: June 2026
Most people with knee pain assume they should rest and avoid movement. That instinct makes sense. If something hurts, moving it feels risky. But for the majority of knee pain conditions, the opposite is true. Gentle, targeted movement is one of the most effective treatments available, and it is free.
Knee strengthening exercises work by building up the muscles that surround and support the joint. When those muscles are strong, they take on more of the load that would otherwise go through the damaged cartilage or inflamed tissues. Less load on the joint means less pain, better stability, and slower progression of conditions like osteoarthritis.
This guide covers the exercises that are most commonly recommended for knee pain, how to do them correctly, and how to know if you are doing too much.
Who Should Do Knee Strengthening Exercises?
These exercises are appropriate for most people with knee pain caused by osteoarthritis, patellofemoral pain (pain behind the kneecap), mild ligament strains, or general joint weakness from inactivity.
They are also used before knee replacement surgery to strengthen the muscles in advance, and after surgery as part of the rehabilitation process.
If you have had recent knee surgery, a significant ligament tear, or a fracture, do not start any exercise programme without clearance from your surgeon or physiotherapist first. The exercises below are appropriate for most knee conditions but not for all.
Stop any exercise immediately if it causes sharp pain, sudden swelling, or a sensation of instability in the joint. Mild muscle ache during or after exercise is normal. Pain in the knee itself is a signal to stop.
6 Knee Strengthening Exercises for Knee Pain
These exercises focus on the quadriceps, hamstrings, glutes, and hip muscles, all of which support the knee joint. Start with one set of 10 repetitions on each side and build up to three sets over two to three weeks as your strength improves.
1. Straight Leg Raise
This is the safest starting point for quad strengthening because it works the muscle without putting any load through the knee joint itself.
Lie on your back with one knee bent and foot flat on the floor. Keep the other leg straight. Tighten the thigh muscle of the straight leg so the back of the knee presses gently toward the floor. Lift that leg to the height of the bent knee. Hold for two seconds and lower slowly.
The key is making sure the lower back stays flat against the floor throughout. If your back arches when you lift, the movement is too large. Reduce the range until the back stays neutral.
Sets and reps: 3 sets of 10 repetitions per leg, 3 to 4 times per week.
2. Bridging
Bridges strengthen the glutes and hamstrings, which support the knee from behind and help stabilise the pelvis during walking.
Lie on your back with both knees bent and feet flat on the floor, hip-width apart. Keep your arms relaxed at your sides. Press through your heels and lift your hips until your body forms a straight line from shoulders to knees. Hold for two seconds at the top and lower slowly.
Do not push through the toes or let the knees fall inward. The movement should come from the glutes, not the lower back.
Sets and reps: 3 sets of 10 repetitions. Progress to single-leg bridges when this feels easy.
3. Clamshells
Clamshells strengthen the hip abductor muscles, particularly the gluteus medius. Weak hip muscles are a common but overlooked contributor to knee pain because they affect how the knee tracks during movement.
Lie on your side with your hips and knees stacked and both knees bent to about 45 degrees. Keep your feet together. Slowly rotate the top knee upward toward the ceiling, like a clamshell opening, without letting the pelvis roll backward. Hold briefly and lower with control.
The movement should feel like it is coming from the hip, not the waist. If you feel it mainly in your lower back, reduce the range.
Sets and reps: 3 sets of 10 repetitions per side.
4. Hip Abduction (Side-Lying)
This exercise targets the outer hip muscles directly and is particularly useful for patients with patellofemoral pain or knee instability during walking.
Lie on your side with the bottom knee slightly bent for balance. Straighten the top leg. Flex the top foot so the toes point forward rather than toward the ceiling. Lift the top leg to about 45 degrees, no higher, and lower slowly. Keep the movement controlled throughout.
Sets and reps: 3 sets of 10 repetitions per side.
5. Wall Squat (Wall Sit)
Wall squats build quad strength in a controlled way that many patients find more manageable than free squats because the wall removes the balance challenge.
Stand with your back flat against a wall, feet about 30 to 45 centimetres forward. Slide your back down the wall until your knees are at a comfortable angle, around 30 to 45 degrees of bend. Hold for five to ten seconds and slide back up.
Do not go deeper than 90 degrees of knee bend, especially early in rehabilitation. If you feel pain in the front of the knee, reduce the depth of the squat.
Sets and reps: 3 sets of 5 to 10 second holds, 3 times per week.
6. Step-Ups
Step-ups are one of the most functional knee strengthening exercises because they directly mirror the demands of climbing stairs, which is often one of the first activities knee pain limits.
Stand in front of a low step or stair. Place the affected foot on the step. Drive through the heel of that foot to push your body up, bringing the other foot up to meet it. Step back down slowly and with control. The slow lowering phase (the eccentric component) is where most of the strengthening benefit comes from.
Start with a low step of 10 to 15 centimetres and progress to a higher step as strength improves.
Sets and reps: 3 sets of 10 repetitions per leg.
Stretches to Do After Your Exercises
Stretching after your knee strengthening session helps maintain flexibility and reduces the stiffness that can build up after strengthening work. Hold each stretch for 20 to 30 seconds and repeat two to three times per side.
Hamstring Stretch
Sit on the floor with one leg extended straight and the other bent. Keep your back straight and lean forward gently from the hips until you feel a stretch along the back of the extended thigh. Do not round the spine to reach further.
Quadriceps Stretch
Stand upright holding a chair or wall for balance. Bend one knee and bring the heel toward the buttock. Hold the ankle gently. Keep both knees close together and stand tall. You should feel the stretch along the front of the thigh.
Calf Stretch
Stand facing a wall. Step one foot back and keep that leg straight with the heel pressed into the floor. Bend the front knee slightly until you feel a stretch in the calf of the back leg. This also indirectly reduces tension around the knee by improving lower limb flexibility.
Other Types of Exercise That Help Knee Pain
Knee strengthening exercises are most effective when combined with low-impact aerobic activity. These options keep the muscles and joint active without overloading damaged cartilage.
Stationary cycling moves the knee through a comfortable range repeatedly, builds quad and hamstring strength, and maintains cardiovascular fitness. It is one of the most physiotherapist-recommended activities for knee osteoarthritis.
Swimming and water walking offload the joint almost completely while keeping the muscles working. These are particularly useful during painful flare-ups when weight-bearing exercise is uncomfortable.
Walking on flat, even surfaces at a comfortable pace is appropriate for most people with knee pain. Uneven ground, hills, and prolonged walking on hard surfaces should be introduced gradually.
How to Know if You Are Exercising at the Right Level
This is one of the most common questions patients ask. The short answer is that some discomfort is normal. Pain that stops you is not.
You are exercising at the right level if you feel mild muscle fatigue or ache during the exercise that settles within 24 hours, your pain during the exercise is no more than a three or four out of ten, and you do not notice increased swelling or stiffness the following morning.
You are doing too much if pain during exercise reaches a five or above, swelling is noticeably worse after sessions, or you wake up the following morning feeling significantly stiffer than before you started.
If either of these patterns appear, reduce the number of sets or the range of movement and build back up more gradually.
When to Stop and See a Specialist
Knee strengthening exercises are appropriate for most knee conditions, but some situations need clinical assessment before or instead of exercise.
See a specialist if your knee pain has not improved after six weeks of consistent exercise, if the knee swells significantly after activity, if you hear or feel a pop in the knee followed by pain or instability, if you cannot fully straighten or bend the knee, or if pain is severe enough to limit normal daily activities.
At Bharath Orthopaedics in Chennai, a consultation will identify exactly what is causing your knee pain and whether exercise alone is sufficient or whether additional treatment is needed.
Read more about physiotherapy for knee pain, tips for knee pain relief, or alternatives to knee replacement for a fuller picture of non-surgical knee care options. For appointments, visit our contact page.
Key Points
- Knee strengthening exercises reduce pain by building the muscles that support the joint and take load off damaged cartilage
- The six most effective exercises for knee pain are straight leg raises, bridging, clamshells, hip abduction, wall squats, and step-ups
- Mild muscle ache during exercise is normal. Pain in the knee itself during exercise is a signal to stop and reduce the intensity
- Combine strengthening exercises with low-impact aerobic activity like cycling or swimming for the best results
- If knee pain has not improved after six weeks of consistent exercise, a clinical assessment is needed to identify the underlying cause
- These exercises are appropriate before and after knee replacement surgery as part of a structured rehabilitation programme
Read also Knee Ligament Surgery
