I’ve always found interval training to be one of the most beneficial types of workout in my training arsenal. If you’re not familiar with interval training, it’s a workout where you intersperse short bouts of intensive exercise (usually 200 or 400 meters or so for me = 1:00-1:30) with a period of rest (walking or light jogging). I run my intervals at 5K pace or a bit faster. I have the sense that my personal fitness benefits greatly from running intervals, and there is some evidence that it’s a great way to burn fat as well. The following story from NPR focuses on this latter benefit, and shows that just about anyone, from beginner to experienced runner, can create an interval workout suited to their own ability and fitness goals.
I’ll add that the “catecholamines” referenced in the story are likely epinephrine (adrenaline) and norepinephrine, both of which are secreted in significantly higher amounts during intensive exercise. These hormones have the effect of, among many other things, stimulating the breakdown of glycogen to glucose in liver and muscle, and the release of free fatty acids from fat stores for use as energy. So the scientific logic here is very sound.
Here’s a link to another related story on interval training and fat burning: http://www.sciencedaily.com/releases/2007/06/070627140103.htm