Chapter 7 talks about the Myth of the “Fat –Burning” Zone. Can one really achieve more weight loss or fat loss by resting?
Although the “fat burning” zone is thought of as the time when the body is at complete rest, the amount of energy used (calories burned) is minimal and thus, it is not productive for weight or fat loss. Body fat reduction is achieved by total calories burned and not by the total amount of fat an individual burns. The percentage of calories derived from fats and carbohydrates has to do with the energy systems used at different generalized heart rate zones. Fat and glucose are the main fuel sources for exercise and they are used more efficiently when the body receives enough oxygen. In turn, waste products are produced in the form of carbon dioxide. The ratio of oxygen consumed to carbon dioxide given off gives us the respiratory exchange ratio (RER). Fat and carbohydrate are oxidized (burned for energy) differently in the body. Keep in mind that RER is only an estimate of how the body uses fuel for energy but it does not dictate the total amount of fat or calories and individual burns.
