Attack FAT!

There is a common misbelief that you burn more body-fat with low intensity exercise. The truth is at a lower intensity fat does provide a high percentage of fuel. But overall you can burn a higher total of fat calories by exercising harder.

For example exercising for 1 hour at a HR of 120 will burn about 350 calories. Of these, about half (175) will be fat calories. Conversly if you exercise harder and get your HR up to 160bpm, you may burn about 1,000 calories an hour. At this intensity only about 1/5 will be fat calories. But that is still 200 calories and 25 more than exercising at a lower intensity. So overall not only do you burn more fat calories but nearly 3 times the total calories.

This is doubly significant, because of how your body restocks calories and by how many calories you will burn post exercise. Studies show that when you burn primaly fat calories with lower intensity exercise your body will replinish these first. So your back where you started. Which is why all those lazy people who read or talk on the cell phone during exercise never get any results. For losing body fat, it is best to exercise at the highest level that comfortably sustainable. Don't restrict intensity with the misbelief that it's neccessary to burn fat.