Hi again, Pinky! I had to go get my son from school.
I should have said there's at least 1000 calories stored in your muscles and liver and you can go quite a long while on that stored energy before needing to replensih. Since you are getting up from rest and your body has been in quiet state that doesn't require a great deal of enegy output, and assuming you ate well the previous day, you are good to go. When I used to get up and head straight out to run, I never ate breakfast nor drank anything to fuel up. You actually have additional glycogen stored in your liver and once muscle stores are depleted, we get more from the liver. Next comes fat stores I don't know too many people who are in danger of canabalizing their protein because if anything we eat too much! I am fairly small but I have plenty of fat to use should I run low on glycogen but I rarely exercise for more than two hours and usually for quite a bit less than that.
I wake up and the last thing I want is food. Some people wake hungry and I think you need to listen to what your body wants. I got up at 5:30 and I worked out at 8:30 for just under two hours. I was hungry when I finished and I ate whole wheat pasta with a TBS of pesto and a salad with tomatoes, cukes, red onion, artichoke hearts and olives, tuna and a olive oil vinegarette. I was tired when I was done, but didn't feel like I'd overdone it in any way.
Here's a portion of a college lecture that gives the scientific explanation for energy storage.
"We Store Fuel for Exercise in 3 Different "Tanks"
* Chemical energy in the body is stored mainly as ATP , glycogen and triglycerides
o ATP (and creatine phosphate = CP) can be used very rapidly but we have only tiny amounts- enough for about 10 sec. (good for sprinting, jumping, lifting)
o Glycogen is stored in the muscles and liver and there is enough for approximately 2 hours- "hitting the wall" when running a marathon is caused by running out of glycogen
o We have lots of energy stored as lipids (triglycerides)- the amount varies from person to person, but there is enough for many days...."
I am going to edit this and add this:
"*The energy value for CHO is 4 kcals/gram. An individual has approximately 20 kcals in the blood, 300-400 kcals stored in the liver, and 1,200-2,400 kcals stored in the muscle. We can see why we want to eat a high CHO diet. We need to replace all that is lost during exercise. The longer the exercise, the more CHO depletion. The depletion of CHO stores can lead to mental and physical fatigue, which can both hinder performance.***"
Of course, the numbers vary according to your size and muscle mass.
Bobbi "Chick's rule!"
http://www.handykult.de/plaudersmilies.de/chicken.gif