I heard that there's a fat burning zone. What is it?

There is such a thing as a fat-burning zone, however it is not what most people think it is. The fat-burning zone myth suggests that slower, or less intense activity, will burn more fat because the body would burn fat as fuel as opposed to other energy sources stored within our muscles. However, the truth is that less intense activity will burn less overall calories and result in less weight loss. Weight loss comes down to calories. Therefore, the more calories you can burn in the time you have to exercise, the better. So don't get stuck in the myth that less intense exercise or activity burns more fat, because it really doesn't. You will burn more calories doing higher intensity activity - and as a result burn more overall fat.

The "fat-burning myth" is an ill conceived notion that body fat is best lost by only performing low intensity cardiorespiratory exercise. However body fat reduction will occur only when there are few calories being consumed than there are being burned. This means that regardless of the intensity of your workouts, your total caloric burn and intake is what ultimately determines whether you will lose weight. The myth of the "fat-burning" zone came about due to something that is termed the Respiratory Exchange Ratio (RER). Your RER reflects what percentage of calories burned are coming from fat. The greatest percentage of calories burned coming from fat is when your RER is at .71. But in order to be at a .71 RER, you are at complete rest such as sleeping or watching TV. If sleeping and watching TV was the best way to lose body fat, the U.S. would not be in a obesity epidemic. Although the majority of the calories burned are coming from fat when exercise intensities are low, the truth is that you are not burning many calories at all and therefore a very inefficient way of losing weight. As RER increases (such as during aerobic exercise) your body starts burning calories coming from carbohydrates. Carbohydrates are your body's primary energy source. But its not where calories are burned that dictates weight loss, it's the total number of calories burned in relation to the number of calories consumed through food and drink. In order to lose stored body fat, maximize your caloric burn throughout the day through exercise and activities of daily living (chores, playing with your kids etc.) and decrease your caloric intake (eat a sensible diet).

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.