First, I want to say "Thank you" to everyone who replied. Your encouragement is just what I needed.
I am going to try it and see how it goes. I will let you know what goes well and what obstacles come my way.
Dana & Dagger, your advice was really helpful. I will tailor the training program, so that my 12 week program is a 24 week one (repeat each week twice). From what you both said, this will be my best bet.
Chris, I will definately check out that article - thank you.
Upbeat, I will also check out the Jeff Galloway program. Thanks for responding!
And, congratulations to all of you who are keeping up with your exercise programs - either running, walking, or any other sport. Good for you! You are an inspiration.