High intensity training is the way to go when it comes to burning fat and building lean muscle. The principle is simple: exert yourself at a high intensity for a certain amount of time and take a rest of equal (or even lesser) duration. The classic example is sprinting for 30 seconds followed by walking for 30 seconds and repeating this about five to ten times.
So how does this type of exercise help you burn fat?
Well, I’m all about the plain and simple explanations, so here’s the biochemistry in a nutshell. High intensity exercise depletes your body’s glycogen stores (that’s the energy from carbohydrates that your body has on deck to be used for immediate bursts of energy). Once these glycogen stores are emptied, your body will resort to fat for energy (it prefers to spare muscle tissue until absolutely needed, such as in the case of multiple days of complete starvation). So, doing high intensity exercise quickly empties your gas tank of carbs, which then forces your body to burn the other fuel – fat – to provide energy for your activities. Best of all, it only takes 10 to 15 minutes (max). As a result, you’ll be leaner in a shorter period of time. Beats the hell out of running on a treadmill at the same speed for 30 minutes to an hour everyday.
Here’s a sample workout for you. All you need is a flight of stairs and a pair of dumbbells.