Hmmm...well I am not in shape but I do have a personal trainer. She has me do circuit training and cardio. On other days we may just take an hour long agressive walk. Any kind of excercise is good. I like Callie's advice. Depends on how many days a week you want to work out. Another worthy investment may be a heart rate monitor. That way you know when doing cardio that you're in the correct range. With weight training...just listen to your body. It's good to be sore the next day but not to the point where you can't move. Just take it easy at first. If you do too much, you could burn yourself out. Maybe keep a little journal to help you understand what works best for you. Good luck!!