Our expert says:
Ok, so two things. First is the knee. If that knee is going to prevent exercise, then yes, you need to see to it first. If it is not going to prevent exercise, and you can for example swim or cycle, then you can start now and deal with it later on.
In terms of what you do, if you go to the fitness page of this site (http://www.health24.com/fitness/Programmes/16-1347.asp) you will see a host of programmes and you can really just pick one of them, depending what you prefer. I think that's the best way to start, and then as you get more comfortable, you can change and modify things to suit you.
The information provided does not constitute a diagnosis of your condition. You should consult a medical practitioner or other appropriate health care professional for a physical exmanication, diagnosis and formal
advice. Health24 and the expert accept no responsibility or liability for any damage or personal harm you may suffer resulting from making use of this content.