After knee replacement, exercise can improve joint strength, flexibility, and balance. While there are general guidelines on the best exercises, it’s best to speak with your doctor about what to start with, when to begin, and how often to do them.

Experts recommend staying active if you have osteoarthritis of the knee, especially after knee replacement surgery

Exercise can help:

  • strengthen your knee muscles and keep you mobile in the long term
  • manage your weight
  • relieve stress

In most cases, you can resume many of your typical activities after about 12 weeks, but you may be able to add in some exercises sooner to help you heal with your doctor’s approval.

According to the American Academy of Orthopaedic Surgeons (AAOS), your doctor or physical therapist may recommend doing both of the following once you recover from surgery.

  • exercising for 20–30 minutes, 2–3 times
  • walking for 30 minutes, 2–3 times

In other words, you could be exercising for 2 hours each day.

Your doctor will provide recommendations for activity based on your needs and overall health. In general, they will recommend low impact exercises over high impact versions that can add stress to your knees.

Here are a few examples of low impact activities and sports:

  • Walking: Walking is a great way to strengthen your knee, burn calories, and improve heart health. Start with smaller steps and work your way up to longer distances. Use a pedometer to track progress. However, avoid jogging or running after a total knee replacement as it is high impact.
  • Swimming: Swimming and other water exercises are ideal for those with artificial knees, as they don’t put stress on the joint. You should be able to resume these activities about 3-6 weeks after surgery but always consult with your doctor or therapist first.
  • Dancing: This is a good way to use leg muscles and engage in light aerobic activity. Avoid twisting and abrupt movements that could put your knee out of alignment. Also, avoid high impact movements such as jumping.
  • Cycling: Cycling is a great way to recover knee strength. Start slowly on a flat surface, using either a bike or an exercise machine. The AAOS suggests peddling forward only after you can comfortably cycle backward. Gradually increase your distance and track your time for added challenges.
  • Elliptical: These machines can provide a good workout without placing undue stress on the knees. An elliptical machine is a great alternative to running because you can move faster than walking without the impact.
  • Gentle aerobics: These classes are available at most gyms. Just make sure you skip high impact exercises.
  • Yoga: Gentle yoga stretching can improve knee health and flexibility. But avoid twisting movements and keep your knees aligned with your hips and ankles. Let your instructor know about any limitations to avoid extra strain. If there is pain, change the exercise or take a break.
  • Weightlifting: Lifting weights helps build strength and diminish knee pain. That said, use weights that are appropriate for your size and strength. Check with your doctor before engaging in a weightlifting program. If necessary, consult with a physical therapist or trainer to map out a regimen.
  • Calisthenics: These basic exercises rely on simple, rhythmical movements and help build strength while increasing flexibility. Examples include crunches, pushups, and lunges.
  • Golf: The golf course provides a good way to walk and exercise various lower and upper body muscles. But avoid wearing spikes that could get caught in the ground, and make sure you maintain good balance when you hit the ball. Spend adequate time warming up at the driving range, and use a golf cart once you hit the course.
  • Doubles tennis: This requires less movement than singles, so it’s a good way to exercise without placing undue stress on your knee. In most cases, you can begin playing tennis 6 months following your surgery. Be sure to avoid running and keep your games low impact.
  • Rowing: This provides a good upper body and heart workout while placing minimal stress on the knees. Make sure you adjust the seat on the machine so that your knees are bent 90 degrees or more.
  • Bowling: It’s generally safe to bowl after knee replacement surgery, but you should consider using a lighter ball to reduce stress on your knee. Stop bowling if you begin to feel any pain in your knees.

After surgery, you may be looking forward to moving without pain but nervous that you’ll damage your new knee joint if you participate in physical activity.

Artificial knees are designed to mimic a natural knee. This means that, like a natural knee, they need exercise to function properly.

Exercise will also help you maintain a healthy weight, which will also help reduce the chance of complications. That said, what exercise you can begin with and when depends on how your knee is healing and your overall recovery, as well as on the recommendation of your doctor.

Can you overdo exercise after knee replacement?

It is possible to exercise too much or too hard after a total knee replacement. According to the American Association of Hip and Knee Surgeons (AAHKS), immediately after surgery, you should take it slow with just stretching and gradually add more exercises. This will help strengthen your knee muscles as you heal without causing more damage.

The AAHKS recommends increasing your exercises gradually in three phases: Weeks 1-3, weeks 4-6, and weeks 7-12. In addition, always begin every exercise session with warming up and finish by cooling down. Take over-the-counter pain medication to help with swelling and discomfort. Once you fully heal, it’s a good idea to continue with a maintenance exercise program.

That said, before you begin any exercise program, speak with your doctor to make sure they give you specific recommendations that are right for you, as every person’s case is different.

The AAOS estimates that most people’s knee replacements still function well 15 years after the surgery.

Working out can keep your weight down, which may also help reduce wear and tear on your new knee joints.

That said, rushing into activities before you’ve sufficiently recovered may put you at risk for complications. It’s important to take things slowly and gradually build your way up to a comprehensive exercise routine.

Check with your doctor before engaging in any activities after knee surgery. Above all, stop working out immediately if you feel any knee pain or discomfort.