Originally Posted by
Fat Boy
I think AZ means that he burns a high percentage of fat (as opposed to carbs) at moderate outputs. I do 'bonk rides' everyone once in a while (once or twice a month). I get up in the morning and have no calories (I still have my black tea) and only water with me. I then go ride 1-2 hours at anything from an endurance to SST pace. I do this to get my body to remember that it can just burn fats if it needs to. Doing one of these rides every day would not be good for me overall.
Exactly. Your supply of fat, whether you have recently eaten or not, is essentially unlimited. According to Dr. Stone (our physiologist), depriving your body of carbs encourages it to burn fat, as does feeding it fat. He conducted tests with athletes exercising while intravenous fluids were added to their systems. Adding fat increases fat burning - adding sugars increases carb use. Having the fat, and only the fat, available causes adaptation that improves your ability to burn fat. The limiting factor is the amount of O2 you can burn. You can't burn either without the O2.