I had a left hip replacement and started to use my machine as soon as I got home. It is now three months since my operation and I have recovered marvellously, I am sure the machine is one of the reasons this has happened, I have used it every day since and now I am going on 4 mile walks with ease and also I use my exercise bike for three quarters of an hour every day. I would highly recommend this machine for anyone who is about to have either a knee replacement or hip replacement.