Crispety- I agree with you. I also think that setting concrete goals and writing them down on a calendar also helps.
When you begin to see your progress visually on a calendar after a while it becomes a habit. Experts say that it takes three weeks to develop a habit for something.
In addition, as you progress in your exercise routine, you can also establish fitness goals. For example, if your method of exercise is walking, you can state that you want to walk three miles in forty-five minutes.
As you get faster, write down your completion time. This makes exercise like a game and keeps it fun for you so you will continue and develop a routine.