The Fat-Burning Myth Debunked
There's a lot of controversy out there about exercise and nutrition and what gives you the best results. As fitness professionals, much of our time is spent helping clients separate fact from fiction. One of the most common myths out there today centers around the most effective way to burn body fat.
Myth: If I do my aerobic workouts at a low intensity, I will burn more body fat. It's more effective to work out in the 'fat-burning zone' than if I train at a high intensity.
This is music to many ears; who wouldn't want to work out at a lower-intensity and see better results? However, this myth is sending the wrong message for those concerned about their weight because it doesn't take into account the total number of calories we burn at a higher intensity versus a lower level.
Here's an explanation from the American Council on Exercise:
While it is true that a higher proportion of calories burned during low-intensity exercise come from fat (about 60% as opposed to approximately 35% from high-intensity programs), high-intensity exercise still burns more calories from fat in the final analysis.
For example, if you perform 30 minutes of low-intensity aerobic exercise (i.e., at 50% of your max exercise capacity), you'll burn approximately 200 calories. About 120 of those, or 60%, come from fat. However, exercising for the same amount of time at a high intensity (i.e., 75% of your max exercise capacity) will burn approximately 400 calories, and 35% of them, or 140 calories, will come from stored fat.
So by sticking to the fat-burning zone for their workouts, many individuals are wasting valuable time. Keep in mind that you lose weight and body fat when you expend more calories than you consume, not because you burn fat (or anything else) when you exercise.
The bottom line is all forms of exercise have their benefits, but don't let the 'fat-burn' myth fool you. Low-intensity workouts do, in fact, promote weight and fat loss. You just have to do them for a longer period of time.