Knee replacement surgery is a common procedure to alleviate severe knee pain and restore function caused by arthritis or injury. Successful recovery depends on following a structured exercise program designed to build strength, improve joint mobility, and reduce stiffness. Studies show that post-operative rehabilitation programs significantly improve functional outcomes after knee replacement surgery (Artz et al., 2015).
Beginning exercise immediately after surgery, often within 24 hours, is critical for faster recovery. Early mobilization reduces complications and promotes healing, consistent with recommendations from the American Physical Therapy Association (APTA Clinical Practice Guidelines, 2020). Learn more about Post-Surgery Physical Therapy.
Exercises such as straight leg raises, quad sets, and heel slides effectively improve quadriceps strength and knee range of motion, which are essential for restoring mobility and function. Research confirms that strengthening these muscles enhances walking ability and overall knee performance after surgery (Petterson et al., 2009).
Avoiding high-impact or strenuous activities after knee replacement is necessary to protect the new joint and ensure long-term success. According to the American Academy of Orthopaedic Surgeons, patients should refrain from activities that stress the implant to prevent premature wear (AAOS Patient Guide).
Key Takeaways
- Pre-surgery exercises like chair push-ups and straight leg raises help build muscle strength and prepare your knee for surgery.
- Post-surgery rehab exercises such as ankle pumps, quad sets, and heel slides improve mobility, reduce swelling, and support healing.
- Consistent exercise immediately after surgery, often starting within 24 hours, is critical for a faster and more successful recovery.
- Avoid high-impact or strenuous activities that could damage your new knee joint during the recovery phase.
- Follow your physical therapy schedule and stay patient—full recovery can take months, but steady progress is key.
- Consult healthcare professionals if you experience pain or unusual symptoms to ensure safe rehabilitation.
Knee Exercises – Before Your Joint Replacement Surgery
Chair Push-ups
How to do this exercise:
- Sit comfortably near the edge of a sturdy chair with your feet flat on the floor, hip-width apart.
- Place your hands firmly on the armrests or sides of the chair.
- Slowly push down with your arms to lift your bottom slightly off the seat, engaging your upper body muscles.
- Hold the lifted position for 3 seconds.
- Gently lower yourself back down to the chair.
- Repeat 10 to 15 times, aiming for 2 to 3 sets daily.
Chair push-ups are an effective preoperative knee exercise designed to build upper body strength, improve shoulder stability, and support overall mobility. This low-impact strengthening move is especially useful as part of a pre-surgery knee conditioning routine and helps activate muscles before joint replacement surgery. Strengthening your arms and shoulders through chair push-ups aids in reducing stress on the knee joint and supports easier movement and balance after surgery.
Precautions to keep in mind:
- Avoid chair push-ups if you feel pain in your shoulders, wrists, or arms during the exercise.
- Always use a sturdy chair with armrests to prevent slipping or falling.
- Start slowly and increase repetitions gradually to prevent muscle strain or injury.
Straight Leg Raises / Leg Lifts
How to do this exercise:
- Lie flat on your back on a comfortable surface, keeping one leg bent with the foot flat on the floor.
- Keep the other leg straight and slowly lift it about 12 inches off the ground.
- Hold the lifted position for 3 to 5 seconds, focusing on tightening your quadriceps (front thigh muscles).
- Slowly lower the leg back down without letting it touch the floor completely.
- Repeat 10 to 15 times, then switch legs. Aim for 2 to 3 sets daily.
Straight leg raises are a fundamental exercise to build quad strength and activate the hip flexors, crucial for improving knee extension and overall joint stability after knee replacement surgery. These leg lifts are gentle yet effective, even when your knee feels stiff or swollen, making them an essential part of post-op quad strengthening and knee strengthening leg lifts routines. Sometimes called knee straightening lifts, this exercise improves muscle control and promotes pain-free movement.
Precautions:
- Avoid lifting the leg too high if it causes pain.
- Keep your lower back flat on the floor to prevent strain.
- Stop immediately if you feel sharp pain in the knee or thigh.
Short Arc Quads (Mini Kicks)
How to do this exercise:
- Lie on your back or sit with a rolled towel or small cushion placed under your knee for support.
- Keep your leg straight and slowly lift your foot by straightening your knee about 6 to 8 inches off the surface.
- Hold the lifted position for 3 seconds, focusing on tightening your quadriceps.
- Slowly lower your foot back down.
- Repeat 10 to 15 times, 2 to 3 sets daily.
Short Arc Quads are a low-impact, effective exercise designed to build quadriceps strength and improve knee extension, both vital for enhancing joint mobility and reducing stiffness after knee replacement surgery. This exercise allows controlled knee extension with partial range activation of the quad muscles, making it a safe and essential move for post-surgery knee rehab. Though some may worry about difficulty, starting with small, consistent lifts helps build strength gradually.
Precautions:
- Avoid overextending your knee during the exercise.
- Use a towel or cushion under your knee for added comfort and support.
- Stop immediately if you feel sharp pain in your knee or thigh.
Knee Straightening Exercises
How to do this exercise:
- Sit or lie down with your leg extended straight.
- Gently press the back of your knee toward the floor or bed, aiming to straighten it fully.
- Hold the position for 5 to 10 seconds.
- Relax and repeat 10 to 15 times, 2 to 3 sets daily.
Knee straightening exercises are essential for improving knee extension, which plays a crucial role in walking and overall joint function. After knee replacement surgery, regaining full knee extension helps reduce stiffness, enhances muscle flexibility, and promotes proper joint alignment. This gentle yet effective exercise activates and strengthens the muscles around the knee, encouraging better movement even if stiffness is present.
Precautions:
- Avoid forcing the knee straight if it causes pain.
- Do not hyperextend your knee.
Knee Range of Motion in Sitting Position
How to do this exercise:
- Sit on a sturdy chair with your feet flat on the floor.
- Slowly slide your foot back under the chair to bend your knee as much as possible.
- Hold the bent position for 5 seconds.
- Straighten your leg back out as far as comfortable.
- Repeat 10 to 15 times, 2 to 3 sets daily.
This seated range of motion exercise helps improve knee flexion, which is vital for everyday activities like walking and climbing stairs. Performing the exercise while sitting reduces weight-bearing pressure on the knee joint, making it ideal for early rehabilitation or when swelling is present. Regular practice increases muscle flexibility and joint alignment, helping to reduce stiffness after surgery.
Precautions:
- Move within a pain-free range.
- Avoid sudden or jerky movements.
- Stop if sharp pain occurs and consult a healthcare provider.
Knee Exercises – After Your Joint Replacement Surgery
Ankle Pumps
How to do this exercise:
- Sit or lie down with your legs extended.
- Point your toes away from you (plantar flexion), then pull them back toward your body (dorsiflexion).
- Repeat this pumping motion slowly and steadily.
- Do 20 to 30 pumps every hour while awake.
Ankle pumps are essential for improving ankle mobility and promoting circulation after knee replacement surgery. This simple, low-impact exercise helps prevent swelling and reduces the risk of blood clots by encouraging blood flow through your lower legs and ankles. It’s safe for nearly everyone and can be performed even with limited mobility.
Precautions:
- Avoid quick, jerky movements.
- Stop if you feel sharp pain or discomfort.
Quad Sets / Knee Presses
How to do this exercise:
- Sit or lie down with your leg extended straight.
- Tighten the muscles on the front of your thigh (quadriceps) by pressing the back of your knee gently down toward the floor or bed.
- Hold the contraction for 5 to 10 seconds while keeping your leg straight.
- Relax and repeat 10 to 15 times, aiming for 2 to 3 sets daily.
Quad sets, also known as knee presses, are essential for quadriceps contraction and muscle activation after knee replacement surgery. These gentle, low-impact exercises help improve knee stability by reactivating muscles weakened from surgery or reduced activity. Early strengthening of your quadriceps enhances knee control and supports better walking and standing.
Precautions:
- Avoid holding your breath while contracting muscles.
- Do not force the movement if you feel pain.
Straight Leg Raises (Leg Lifts)
How to do this exercise:
- Lie flat on your back with one leg bent and the other straight.
- Tighten your thigh muscle on the straight leg and slowly lift it about 12 inches off the floor.
- Hold for 3 to 5 seconds, then slowly lower it back down without touching the floor.
- Repeat 10 to 15 times, then switch legs. Do 2 to 3 sets daily.
Straight leg raises help build quad strength, essential for knee stability and improving mobility after knee replacement surgery. They activate key muscles without putting stress on the joint, making them effective even when swelling or stiffness is present. If you feel discomfort, lift your leg only as far as comfortable or ask a therapist for modifications.
Precautions:
- Keep your lower back flat to avoid strain.
- Avoid lifting too high if it causes pain.
- Stop immediately if you feel sharp pain.
Heel Slides
How to do this exercise:
- Lie on your back with your legs straight.
- Slowly slide the heel of your affected leg toward your buttocks, bending your knee as much as comfortable.
- Hold the bent position for 3 to 5 seconds.
- Slide your heel back down to straighten your leg.
- Repeat 10 to 15 times, 2 to 3 sets daily.
Heel slides help improve knee flexion (bending), which is essential for daily activities like walking and climbing stairs. This exercise gently increases your knee’s range of motion and flexibility after surgery. It’s safe and effective even if you experience some swelling or stiffness.
Precautions:
- Avoid forcing the bend if it causes pain.
- Move slowly and smoothly to prevent injury.
- Stop if you feel sharp or severe pain.
Short Arc Quads (Mini Kicks)
How to do this exercise:
- Lie on your back or sit with a rolled towel or small cushion under your knee for support.
- Keep your leg relaxed and slowly straighten your knee by lifting your foot about 6 to 8 inches.
- Hold the straightened position for 3 seconds while tightening your quadriceps (thigh muscles).
- Slowly lower your foot back down.
- Repeat 10 to 15 times, 2 to 3 sets daily.
Short Arc Quads help build quad strength and improve knee extension, which is crucial for stability and reducing stiffness after knee replacement surgery. It’s a low-impact exercise suitable even if your knee feels swollen or stiff. Start gently and increase as your strength improves.
Precautions:
- Avoid hyperextending your knee.
- Use a towel or cushion for comfort and support.
- Stop if you feel sharp pain or discomfort.
Knee Range of Motion in Sitting Position
How to do this exercise:
- Sit comfortably on a sturdy chair with your feet flat on the floor.
- Slowly slide one foot back under the chair to bend your knee as far as comfortable.
- Hold the bent position for 5 seconds.
- Then, slide your foot forward to straighten your leg as much as possible.
- Repeat 10 to 15 times, 2 to 3 sets daily.
This seated exercise helps improve knee flexion (bending) and extension (straightening) without putting weight on your knee. It’s ideal for early rehab after knee replacement surgery because it gently promotes flexibility and reduces stiffness while you remain supported.
Precautions:
- Move within a comfortable range without forcing the knee.
- Avoid quick or jerky movements.
- Stop if you experience sharp pain and consult your healthcare provider.
How long should you do exercises after knee replacement?
After knee replacement surgery, exercises are typically recommended immediately or within the first 24 hours to start gentle movements such as ankle pumps and quad sets. The most intensive rehab phase usually lasts 6 to 12 weeks, focusing on regaining strength, range of motion, and function with regular physical therapy sessions. Exercise frequency is generally daily in the beginning, tapering to several times a week as recovery progresses, with intensity gradually increasing as pain and swelling decrease.
Many patients continue with some form of knee exercises for 6 months to a year or longer to maintain joint health and prevent stiffness. Following the recommended rehab duration and physical therapy schedule is key for long-term recovery after knee replacement.
How to reduce stiffness after knee replacement?
To reduce stiffness after knee replacement, start by gently moving your knee through its range of motion several times a day, using exercises like heel slides and knee bends. Apply ice packs regularly to reduce inflammation and swelling around the joint. Engage in gentle stretching routines to maintain and improve flexibility without causing pain. Keep your leg elevated when resting to help decrease swelling and stiffness.
Consistently perform low-impact strengthening exercises, such as quad sets and ankle pumps, to support joint mobility and reduce stiffness. Remember to pace yourself and avoid overexertion, gradually increasing activity as your knee improves. If stiffness persists, consult your healthcare provider for tailored advice or physical therapy.
When to start physio after knee replacement?
Physical therapy usually begins within the first 24 to 48 hours after knee replacement surgery, often starting with gentle exercises like ankle pumps and quad sets. Early rehabilitation focuses on reducing swelling, restoring movement, and preventing complications. As recovery progresses, physiotherapy sessions become more intensive, targeting strength, balance, and functional mobility. The timeline for physio varies but generally continues for several weeks to months, depending on individual progress and goals. Starting physiotherapy promptly and following a structured rehab plan is essential for optimal recovery after knee replacement.
What exercises can you not do after knee replacement?
- High-impact activities like running or jumping
- Deep squats or lunges that put excessive stress on the knee
- Twisting or pivoting movements that strain the joint
- Heavy weightlifting exercises involving deep knee bends
- Kneeling or prolonged pressure on the knee
- High-intensity sports such as basketball, football, or tennis
- Stair running or jumping down stairs
Avoiding these exercises helps protect your new knee joint from damage and ensures a safer, longer-lasting recovery.
Frequently Asked Questions
What is Knee Replacement Surgery?
Knee replacement surgery involves removing damaged or worn parts of the knee joint and replacing them with artificial components to relieve pain and restore function.
What is the best exercise for a total knee replacement?
The best exercises focus on rebuilding quadriceps strength and improving knee range of motion, such as straight leg raises, heel slides, and quad sets.
What is the biggest complaint after knee replacement?
The most common complaint is persistent stiffness and difficulty bending the knee fully during the early recovery phase.
How many physio sessions after knee replacement?
Most patients attend 6 to 12 physical therapy sessions, but the number varies based on individual progress and surgeon recommendations.
What are the top mistakes patients make after knee replacement?
Common mistakes include pushing too hard too soon, skipping exercises, ignoring pain signals, and failing to follow rehab protocols.
What is the fastest way to recover from a knee replacement?
Consistent exercise, following your rehab plan, managing pain and swelling, and staying active with professional guidance help speed up recovery.