Wed, Dec-02-09, 14:13
|
 |
Dog is my copilot
Posts: 1,448
|
|
Plan: paleo/lowcarb
Stats: 210/162/145
BF:
Progress: 74%
Location: Olympia, WA
|
|
Quote:
|
Originally Posted by Carne!
This is very interesting. I am extremely new to this subject and don't quite understand....why is it that HIT exercise would empty the glycogen stores? I do 1 hour of high intensity anaerobic and aerobic exercise 3x a week. Would this be useful in depleting the stash of glucose as well? And why is it important to do so? Does it then get stashed as fat?
|
It has to do with the difference in metabolism between different types of muscle fibers. Glycolytic fast twitch fibers, which are only activated by high intensity demand, consume the most glucose. Glucose that is cleaved from glycogen inside muscle cells does not leave the muscle. It's either metabolized inside the cell or the unused portion is converted back to glycogen. If it's consumed it will be converted to pyruvate (substrate for the Krebs cycle) and ends up excreted as water/CO2 or eventually recovered from excess lactate at a high net energy cost (the Cori cycle).
Exercise that you can keep up for an hour isn't HIT. Any exercise that fatigues any fibers will consume some glycogen but HIT does this very rapidly. |