Exercises Before Knee Replacement: What to Do Before Surgery

By Emma - The Hip & Knee Physio

If your knee replacement is booked, it can be tempting to think your job is simply to wait for surgery.

Your knee hurts. Walking may already be difficult. You know the joint is going to be replaced anyway, so why bother strengthening it now?

Because surgery changes the joint surfaces, but it does not instantly restore the strength, movement, fitness and confidence you may have lost while living with knee arthritis.

The weeks before knee replacement can still be useful for maintaining strength, movement and activity tolerance, as long as exercise is matched to what your knee can reasonably handle.

This is often called prehabilitation, or prehab.

I am Emma Glynn, an APA Titled Musculoskeletal Physiotherapist in Camberwell. I work exclusively with hip and knee conditions, including people preparing for knee replacement and people rebuilding afterwards.

If you are still managing knee osteoarthritis before surgery, you may also find my knee osteoarthritis page helpful.

In brief

Exercise before knee replacement commonly focuses on maintaining or improving:

• Quadriceps strength

• Hip and calf strength

• Knee movement

• Walking capacity

• General fitness

• Confidence with exercises you may use after surgery

• Familiarity with walking aids or stairs if needed

Research on knee replacement prehab is mixed. Some studies report improvements in strength, function or early recovery, while others show smaller or less consistent benefits after surgery.

The useful message is not that prehab guarantees a faster recovery. It is that staying as strong and active as your knee reasonably allows gives you a better starting point than deliberately becoming less active while waiting.

Why exercise before knee replacement?

People waiting for knee replacement have often spent months or years gradually reducing activity because of pain. That is understandable. A painful knee tends to make you do less. Sadly, muscles are very literal creatures. Give them less work for long enough and they become weaker.

You may notice that you:

• Walk less

• Avoid stairs

• Use your arms more to get out of chairs

• Stop going to the gym

• Avoid longer outings

• Limp more by the end of the day

• Lose confidence loading the painful leg

That matters because after knee replacement, you will need those same muscles to help you:

• Get out of bed

• Stand from chairs

• Walk with an aid

• Manage stairs

• Regain knee movement

• Rebuild normal walking

• Progress back into daily activity

Prehab is not about fixing the arthritic knee before surgery. It is about maintaining as much useful capacity as possible before the operation.

Does prehab actually improve knee replacement recovery?

This is where the evidence needs honesty.

There is no compelling evidence that one specific prehab program dramatically transforms everyone’s knee replacement recovery. Some research suggests prehab may improve selected outcomes, such as strength, function or early post-operative capacity, but study results vary.

So I would not tell someone:

“Do these exercises and you will recover faster.”

A better and more defensible message is:

“Use the time before surgery to maintain strength, movement and fitness where possible, and learn how to exercise the knee appropriately.”

Prehab is best viewed as preparation, not a guarantee.

That preparation can still matter. If your knee is painful and you are doing less, the weeks before surgery can become a period of avoidable deconditioning. The aim is to reduce that where possible.

What should you work on before knee replacement?

1. Quadriceps strength

The quadriceps are the large muscles at the front of your thigh. They help straighten the knee, stand from a chair, climb stairs and control the knee while walking.

Quadriceps weakness is common in people with knee osteoarthritis, particularly when pain has reduced activity.

Maintaining quadriceps strength before surgery is one of the most practical pre-op goals.

2. Hip strength

Your hip muscles contribute to walking, standing, stairs and balance. If your hip muscles are weak, the knee often has less support during everyday movement.

Maintaining hip strength can make the early period after surgery more manageable, especially when the operated knee is swollen, sore and making its opinions known.

3. Calf strength

The calves help with walking, balance and push-off. They are easy to forget because apparently rehabilitation needed another muscle group to supervise.

Calf strength is not the headline act before knee replacement, but it still matters for walking confidence and lower limb function.

4. Knee movement

Your arthritic knee may already be stiff. You do not need to force the knee aggressively into painful ranges, but maintaining the movement you have can be useful.

Knee straightening is especially important for walking. If your knee does not straighten well before surgery, it is worth discussing this with your surgeon or physiotherapist.

5. General fitness

Depending on what your knee tolerates, activities such as walking, cycling, swimming or pool exercise can help maintain general fitness before surgery.

You do not need to become an endurance athlete in the month before a knee replacement. The goal is simply to avoid unnecessary loss of fitness while keeping symptoms manageable.

Five exercises commonly used before knee replacement

These are general examples, not a personalised program. Your exercises may need to change depending on pain, swelling, medical history, current strength and instructions from your surgeon.

The right exercises before knee replacement should challenge the leg without repeatedly causing a major flare.

1. Sit-to-stand

Sit-to-stand is one of the most useful functional strength exercises because standing from a chair is something you will need to do repeatedly after surgery.

How to do it:

1. Sit towards the front of a firm chair.

2. Place your feet comfortably underneath you.

3. Lean slightly forwards.

4. Stand up using your legs as much as comfortably possible.

5. Sit back down slowly.

Start with a chair height that feels manageable. If a low chair causes significant knee pain, use a higher chair or add a cushion.

A starting dose might be 2 to 3 sets of 6 to 12 repetitions, depending on your capacity.

2. Seated knee extension

This exercise targets the quadriceps directly.

How to do it:

1. Sit in a chair.

2. Slowly straighten one knee.

3. Pause briefly near the top.

4. Lower the leg with control.

If bodyweight is too easy, resistance can sometimes be added using an ankle weight or gym machine.

The exercise should feel like meaningful work for the thigh without repeatedly provoking a major knee flare.

3. Calf raises

Calf raises help maintain calf strength, balance and walking capacity.

How to do it:

1. Stand holding a bench or chair for support.

2. Rise onto your toes.

3. Pause briefly.

4. Lower slowly.

Try 2 to 3 sets of 8 to 15 repetitions.

If two legs are easy, the exercise may be progressed by shifting more weight towards one leg, but only if it is safe and well tolerated.

4. Step-ups

Step-ups can help prepare for stairs and strengthen the quadriceps and hip muscles.

How to do it:

1. Use a low step.

2. Place one foot onto the step.

3. Push through the leg and step up.

4. Lower back down with control.

A lower step is often more comfortable for an irritable arthritic knee.

The goal is controlled loading, not finding the tallest object in the house and declaring war on it.

5. Cycling or walking

Cycling and walking are not technically strength exercises, but both can help maintain general activity before surgery.

A stationary bike is often useful because resistance and duration can be adjusted easily.

Walking may also be appropriate, but consider:

• Distance

• Hills

• Speed

• Surfaces

• Rest breaks

• How the knee responds later that day

• How the knee feels the next morning

If 45 minutes produces a substantial flare every time, three shorter walks may be better tolerated.

What if these exercises hurt?

Some discomfort does not automatically mean you are damaging the knee.

People awaiting knee replacement generally already have a painful joint, so expecting every exercise to feel completely symptom-free may not be realistic. The important part is the response.

A useful pre-op exercise dose should feel manageable and should not leave your knee clearly worse the next day.

I would consider modifying an exercise if it repeatedly causes:

• A sharp increase in pain

• Substantial swelling

• Worsening limp

• Reduced knee movement

• Symptoms that remain clearly elevated the next day

• Loss of confidence walking afterwards

You might change:

• The resistance

• Range of movement

• Number of repetitions

• Number of sets

• Exercise frequency

• The exercise itself

The aim is to find enough exercise to maintain or build capacity without turning every session into a two-day flare. A bold and unpopular concept, apparently.

Should I keep walking before knee replacement surgery?

Usually, staying active within your tolerance is sensible unless your surgeon has advised otherwise.

Walking can help maintain:

• Cardiovascular fitness

• Leg strength

• Confidence

• General activity tolerance

• Independence before surgery

But there is no prize for limping through kilometres simply because walking is considered healthy.

If longer walks consistently aggravate the knee, try modifying:

• Distance

• Terrain

• Pace

• Rest breaks

• Frequency

• Timing around strength sessions

You may also substitute some walking with cycling or pool exercise if those are better tolerated.

If you are still working out how much walking is appropriate, my guide to knee arthritis and walking may be useful.

What if my knee becomes swollen after exercise?

A knee with advanced osteoarthritis can become reactive after increased activity. A small and temporary response may be manageable. Repeated substantial swelling suggests the exercise or overall activity dose needs reviewing.

Your knee responds to the total amount of load across the day, not just the exercise session you are thinking about.

A strength session might be perfectly reasonable in isolation, but perhaps not after a long walk, several hours of gardening and an ambitious trip through Chadstone. The knee is petty like that.

If swelling appears after exercise, consider:

• Reducing exercise volume

• Reducing walking distance that day

• Avoiding hills temporarily

• Splitting one long activity into shorter blocks

• Using gentle movement rather than complete rest

• Speaking with your GP, surgeon or pharmacist about symptom management if needed

If persistent knee swelling is a problem, my guide to knee swelling that won’t go away

explains this in more detail.

What about knee arthritis exercises I was already doing?

If you already have an exercise program for knee osteoarthritis, you may not need a completely new collection of exercises just because surgery has been booked.

Many of the same principles still apply. You may simply need to adjust the program around:

• Current pain

• Swelling

• Surgery date

• Current strength

• Walking tolerance

• What you will need immediately after the operation

• Your surgeon’s instructions

You can read my broader guide to knee arthritis exercises if you are still managing knee OA before surgery.

The dedicated knee osteoarthritis page also explains the broader non-surgical management approach.

How often should you exercise before knee replacement?

There is no universal schedule.

For many people, a practical program may include strength work around 2 to 3 times per week, alongside tolerable physical activity on other days.

The exact dose depends on your starting point.

If you have barely exercised for months, suddenly beginning heavy daily training two weeks before surgery is unlikely to be a masterstroke.

Start at a level you tolerate and build gradually if your knee allows.

A simple pre-op week might include:

• Two strength sessions

• Short regular walks

• Gentle range-of-motion work

• Cycling or pool exercise if walking is limited

• Rest or lower-load days after bigger efforts

The plan should help you arrive at surgery prepared, not exhausted and inflamed.

Should I stop exercising just before surgery?

You do not normally need to stop all exercise several weeks before surgery simply because the operation is approaching, unless your surgeon has advised that.

However, the final days before surgery should not be used for heroic training sessions.

The priority is arriving at surgery:

• Reasonably rested

• Without a major exercise-induced flare

• Following your surgeon’s pre-operative instructions

• Medically prepared for the procedure

Your hospital or surgeon may give specific instructions about medications, fasting, skin preparation, illness, wounds, dental work and what to do immediately before surgery. Those instructions take priority over general advice in a blog.

What else should you prepare before knee replacement?

Exercise is only part of preparation.

The weeks before surgery are also a useful time to think about what the first couple of weeks at home will look like.

Prepare your home

Depending on your circumstances, consider:

• Keeping frequently used items within easy reach

• Setting up a supportive chair that is not too low

• Clearing pathways through the house

• Removing obvious trip hazards

• Organising help with shopping, meals or household tasks

• Planning transport to and from hospital

• Checking bathroom setup if needed

• Asking the hospital team about equipment recommendations

No, this is not glamorous. Neither is tripping over a rug with a new knee. Practicality wins.

Understand your walking aid

Your hospital may provide or recommend crutches, a walking frame or walking sticks.

Knowing how to use the appropriate aid before surgery is much easier than learning while your new knee is swollen, painful and giving unsolicited feedback.

Ask your surgical team:

• What walking aid will I use after surgery?

• How much weight can I put through the leg?

• Will I need to practise stairs?

• When should I expect to progress away from the aid?

• Who should I contact if walking feels unsafe?

Know your early rehabilitation plan

Before surgery, it is worth asking:

• When should outpatient physiotherapy begin?

• What exercises should I do immediately after surgery?

• What knee range should I be aiming for early?

• What are my wound instructions?

• When can I drive?

• Are there specific restrictions?

• Who should I contact if I am worried?

Being familiar with the early plan can reduce anxiety and make the first few weeks feel less like you have been handed a knee and a vague instruction manual.

What happens after surgery?

Once the operation is complete, the priorities change.

Early rehabilitation commonly involves:

• Managing swelling

• Regaining knee movement

• Activating the quadriceps

• Safe walking

• Progressing away from walking aids

• Building confidence with stairs

• Gradually rebuilding strength

Recovery then progresses over several months rather than ending once the wound heals.

My Knee Replacement Recovery Timeline explains what rehabilitation commonly looks like from the first week through to 6 to 12 months after surgery.

Do I need physiotherapy before knee replacement?

Not everyone needs a lengthy supervised prehab program.

If you are already exercising confidently, your knee is relatively settled and you understand what you need to do, a simple program may be enough.

A pre-operative physiotherapy assessment may be more useful if:

• You are unsure which exercises are appropriate

• Your knee keeps flaring after activity

• You have become substantially weaker

• Walking has reduced significantly

• You have lost knee movement

• You are unsure how hard to exercise

• You want help planning the transition into post-operative rehab

• You have other issues, such as hip, back or opposite knee pain

The aim is not to convince you that you need endless appointments before surgery. It is to identify what is most worth working on with the time available.

What should you focus on before your knee replacement?

If your knee replacement is already booked, you do not need to spend the waiting period trying to turn an arthritic knee into a normal knee.

The operation is happening for a reason.

Instead, focus on what you can influence:

• Maintain or improve leg strength where possible

• Keep the knee moving as comfortably as possible

• Maintain general activity and fitness

• Avoid unnecessary deconditioning

• Understand the early post-operative plan

• Prepare your home and support

• Follow your surgeon’s instructions

Prehab does not guarantee an easier recovery, but there is little advantage in deliberately becoming weaker while waiting for surgery.

If you have an upcoming knee replacement and would like an individual exercise plan before surgery, you can book a knee physiotherapy assessment with me in Camberwell.

Emma

References

Adebero, T., Omana, H., Somerville, L., Lanting, B., & Hunter, S. W. (2024). Effectiveness of prehabilitation on outcomes following total knee and hip arthroplasty for osteoarthritis: A systematic review and meta-analysis of randomised controlled trials. Disability and Rehabilitation, 46(24), 5771–5790. https://doi.org/10.1080/09638288.2024.2313128

American Academy of Orthopaedic Surgeons. (2020). Preparing for joint replacement surgery. OrthoInfo. https://orthoinfo.aaos.org/treatment/preparing-for-joint-replacement-surgery

American Academy of Orthopaedic Surgeons. (n.d.). Total knee replacement exercise guide. OrthoInfo. https://orthoinfo.aaos.org/recovery/total-knee-replacement-exercise-guide/

Karimijashni, M., Yoo, S., Barnes, K., Lessard-Dostie, H., Ramsay, T., & Poitras, S. (2025). Prehabilitation in patients at risk of poorer outcomes following total knee arthroplasty: A systematic review. The Journal of Arthroplasty, 40(5), 1367–1376. https://doi.org/10.1016/j.arth.2024.10.132

Keogh, J. A. J., Keng, I., Dhillon, D. S., Bourgeault-Gagnon, Y., Simunovic, N., & Ayeni, O. R. (2025). The effects of structured prehabilitation on postoperative outcomes following total hip and total knee arthroplasty: An overview of systematic reviews and meta-analyses of randomised controlled trials. Journal of Orthopaedic & Sports Physical Therapy, 55(5), 344–365. https://doi.org/10.2519/jospt.2025.13075

Medical disclaimer

This article provides general educational information only and is not a substitute for individual medical advice, diagnosis or treatment. Always follow the instructions of your surgeon, GP and hospital team before and after knee replacement surgery. Seek urgent medical review if you develop severe or worsening pain, inability to weight-bear, fever, chest pain, shortness of breath, calf swelling, wound concerns, sudden neurological symptoms, or symptoms that concern you.