Eazy Tip
 

It works fasted.
The theory behind fasted cardio is that if the body is low in carbs, it will turn to fat for energy. I agree with this premise and walking is the perfect form of exercise for it.

Where everybody seems to screw up is by trying to perform HIIT cardio while fasted, which isn't smart because you'll burn a lot of muscle –assuming you have a decent amount of muscle to begin with.