Ask a PT Response: "Are you currently seeing a physical therapist or just doing exercises at home independently? If you are not seeing a PT, I would suggest you get a referral from your doctor to go see a PT. If you are, talk to your physical therapist about the exercises you are doing and your frustration about your slow progress. He or she may be able to modify or add additional exercises to your program. In regards to damaging your knee replacement, you should be fine as long as you are following your doctor's and physical therapist's recommendations and are not kneeling on the involved knee or twisting at the knee. In addition, I would also recommend that you have a discussion with your doctor about the medications you are taking and the negative effect they may be having on your level of energy. He or she might be able to swith the medications to something with less intense side effects. Best of luck to you."