Originally Posted by
bfloyd6969
Thanks for the replies, I am understanding better. However, one thing I am still unclear on - higher intensity rides will burn more calories, but these are calories from stored glycogen rather than stored fat. So, will the fat continue to stay because I am not using it for the fuel source with these harder rides? I'm sure I'm just missing the big picture here and it will click soon....
From what I understand, pure glycogen burning only happens when you are in anaeroabic phase, which one couldn't sustain for longer than several minutes. Cycling is still mostly aerobic and you will burn both glycogen and fat and other stuffs. With high intensity in the aerobic phase, you'll burn more glycogen than fat and eventually deplete the glycogen sooner. With the same amount of riding time, you are prob burn more fat when riding at high intensity even though it is proportionally lower in percentage. For example, low intensity at 500 cal/hr burning 70% fat/30% glycogen will equal to 350 calories from fat; high intensity at 1000/hr burning 40% fat/60% glycogen would equal to 400 calories from fat. Note: this is just a number I made up to illustrate the point. What I found is with high tensity exercise I get extremely hungry afterward and tends to overeat. With lower intensity, eating afterward is optional. Like chasm said, this is not about performance.