Walking on a treadmill is a great cardio exercise. You can increase your stamina, strengthen your bones and muscles and you can have a lot of fun – put on some good music to keep you going. Treadmill fitness walking also helps you lose body fat and stay in shape. Walk at a normal pace, speed walk or even a comfortable jog and burn off those calories. There is far less impact on your joints and back when you walk on a treadmill and not on a hard surface.