In order to achieve your fitness goals, you need to exercise as per a schedule that allows you to advance slowly yet consistently. Of course, if you have the benefit of working under the guidance of a fitness trainer then you work under a program and a schedule. A fitness trainer will advise you on how to get the best out of your workout and set up a program for you to follow.
Alternatively, if you visit a gym then you also get the benefit of a workout plan. The instructors there can just set a program for you to follow, keeping in mind your goals and your current state of health.
However if you work out at home on a treadmill you need a workout program that will guide you towards your goals. Simply buying a treadmill and running on it is not going to help you a lot, as there is no way you can monitor your progress or set a target. Instructors of The American Council on Exercise's Group have said that treadmill exercise is the simplest and most effective form of exercise.
There are various workout programs for treadmills that you can follow. These programs will help you to tone your body, exercise your muscles and put you back into shape. The best way to setup a workout program for yourself is to consult a fitness expert or an instructor. In case you cannot have the benefit of that, then you can access a number of workout programs from the internet.
Remember that a workout program provides you with a sense of direction and helps you to achieve your goals in a more organized manner than you would if you workout without a plan. You set your goals and you work in order to achieve them.