Fat-burning zone and why it is not the best way to burn fat

the only problem I see is they choice long distance cyclists for been training for over 3 years. I wonder if the people who burn fat at a higher rate are people who been training longer than other ones. If I am not mistaked the idea of training is to train your body to use your fat stores more than your carb stores.

I agree with your skepticism about the study subject selection, but not for the same reason. Athletes in the study have been endurance athletes for at least three years, which is a long time to be training compared to beginners. A lot of the physiological adaptations associated with endurance training that have not occurred in beginners have had a long time to happen and become the norm for those athletes. Do they burn more fat when they exercise? Maybe. But that is not the question the study attempted to answer. The study measured the interval of exertion at which fat burning is at its maximum regardless of the actual amount of fat burnt. The empirical amount of fat burnt per individual was not determined.

The study found that the fat-burning interval (or zone) varies quite a bit among the athletes tested and that it also varies because of other factors--amount of carbs consumed being one of them. The point you brought up made me question whether a group of beginners carrying extra weight would show the same variability of fat-burning zone range. It could very well have turned out that a group of couch potatoes starting out would have a very consistent FBZ range. The article does not address this point, so I guess it is geared at a more advanced athlete.

This brings up a point that I get snagged on repeatedly while researching fitness and exercise. Studies and, more importantly, advice out there is based on assumptions that a person has a certain level of fitness or a certain skill. Most of the time these assumptions are not stated, which can lead the person following this advice down the wrong path or, at worst, to injury. (I can give several examples if anyone is interested.)