I'm a 62 years old professional who spends all my work hours seated. I had back surgery June 2008. It was successful in alleviating the severe pain but I still have constant pain which varies in intensity. I have gained weight and am very unconditioned. I thought bike riding might be helpful to get me strong and conditioned as well as leaner (). I also plan on using a treadmill. I haven't ridden since a child but many streets in our area are good for bike riding. I need to get a bike which is comfortable for me and one I feel stable riding. I'm hoping to get inspired by all of you and get suggestions for bikes etc.