I started on a recumbent bike. Low resistance. Worked up. I have bad knees for reference. I started this about 4 months ago. Now I hit the bike, still on a low resistance, for about 45 minutes every other day. On workout/weights days, I use the bike for 30 minutes with pretty tough resistance (Level 5 for 10 minutes; Level 4 for 10 minutes; Level 5 for 10 minutes; it's pretty much a 30 minute uphill...that's my leg training as I can't stand due to back issues). Legs are toned, actually showing some muscles mass increase as well. Here's the thing...if you do this uphill, work up to it. I did over months to get to this point. Start low on it, as on anything else like Keith says, and work up. In other words, don't be a hero! :)

A partner in back pain crime. Ha! I actually do a 10 min low impact ab workout video, cart out most carbs to let the protein/fat diet burn off as much fat as possible, and add some pretty good cardio bike rides (with and without resistance depending on the day). Working so far as I workout from home. I like your suggestions, but I don't go anywhere to machines. I really like your idea...wish I had those at home!