"The Fun Theory" and Fitness
I came across this video and website the other day and liked how you could apply the concept (The Fun Theory) to many activities, enjoyable, monotonous or boring, and come to the same conclusion:

"something as simple as fun is the easiest way to change people’s behaviour for the better. Be it for yourself, for the environment, or for something entirely different, the only thing that matters is that it’s change for the better."
You can visit the website http://www.thefuntheory.com/ to see a couple more videos on the topic.

Making fitness and exercise fun and exciting greatly increases the likelihood that you will actually do it.

A few easy and great ways to keep things fun and exciting while training is to do it with a friend, sibling, or a spouse - It keeps things moving, creates a great training atmosphere, and it allows you to progress and accomplish you goals with someone who can push you and keep you accountable!

I realize that some people like to run, some will do it and some hate it. By simply joining an adult league for basketball, soccer, etc, playing flag football with the family on Sunday or playing a sport at school, you will be running and getting great exercise, all while having fun and not actually thinking about just running. That is just one example, there are innumerable possibilities.

Find something you like, stick to it, and you'll be headed in the right direction!