The Cardio King
Change it up
One of the most important aspects to a cardio workout is changing it. Most people get bored with exercise simply because they pop these DVD's in and do the same thing everyday. Imagine if you had to read the same book everday, would that be fun. No way, so why would you do the same workout everyday. Most people don't realize what they are doing. You have to make it fun in order for it to work.
Try to have at least 4-6 different exercises.
Make sure the you are reaching your target heartrate. If you don't you are not getting the most out of it. Why do something just to do it. Your goal is to burn fat and it is real difficult to do that without reaching your target zone.
Take it outside
Don't just stay in the gym. Change it up and take it on the run. Try doing some intense walking or some bike riding. Play some basketball in the park. Make it fun and interesting, that's the only way you will keep it up.
I hope these two tips help to intensify your cardio workouts. Make sure that when you finish it, you say man that was a great workout. If you don't you could have done much better.