Glad to see your getting out there and taking action. Personally I believe cycling saved my life, and my cardiologist agrees. Four years ago I was riding and had some problems with my chest burning, 5 stents and 1 angioplasty later I'm symptom free. The doc told me hard exercise brings problems to light quicker and before more damage is done, I believe that is true. As said by others before, tell the doc what you intend to do, get advice and personal guidelines. Don't do hills at first, you'll get discouraged. At 202 lbs. hills are still my toughest adversary, but I'm not afraid of them anymore. I curse at them on the way up and it keeps me going. The key with doing hills is recovery time. If you can recover from repeated hills, which I can now do, you won't fear them. Remember, don't make yourself miserable out there....have fun....and you won't give up. Good Luck !!!