First, for the upper body strength, you might want to do push ups. They tone the muscles in the upper body. If they are hard for you, begin with having your knees on the ground to do the push-ups. Then gradually work your way up until you can do them regular. For the legs, I would suggest 3 things: Walking, Jogging, and Swimming. Those 3 will tone the leg muscles and Swimming can provide some extra excercise too. :)