Six jours

That's a blood glucose issue. Blood glucose drops and you get funky. Were your blood glucose to get "fully depleted" you would collapse and shortly die. So I don't think that's what he meant.

I think what he's saying is that his liver glycogen stores rapidly become "fully depleted", and this is fairly accurate. Liver glycogen is our most effective and accessable energy store, but it doesn't last for more than a few hours, at which point our bodies turn to other sources. This is why A) the huge pasta meal the night before is of limited utility (what can't be stored as liver glycogen will be converted to fat, and you've probably already got enough of that) and B) eating during the ride is so important -- once the liver glycogen is gone, the body will look to get glucose into the bloodstream any way it can. If you can't provide a steady supply from your digestive system, your body will start burning fat (makes us happy afterwards, but is pretty inefficient while riding) or muscle (which is bad. If you smell ammonia after the ride, you've been catabolizing muscle.)

</lecture>

supcom

Some of my secrets:

Ride my own ride at my pace. Don't try to keep up with faster riders unless maybe it's a 200k brevet and I know I can handle the extra fatigue later.

Enjoy the scenery. The first sign that I am working too hard is finding myself concentrating too much on the road at the expense of seeing the sights around me.

If at all possible, review the course map beforehand. Knowing the route ahead of time, will go a long way toward avoiding bonus miles. You may even find a cue sheet error that the organizer didn't catch!

Carbonfiberboy 

That's not "fully depleted". That's just low blood sugar. You have hypoglycemia. I have it myself. I thought I was getting diabetic or something so I went in for a checkup and got a glucose tolerance test.

What happened to me is that I got carried away with all that low-fat diet nonsense that used to be all the rage and tried to eat a 10% or less fat diet. That made my pancreas overly sensitive to carbos, so it would make too much insulin, which then took my blood sugar down too low. I was fine riding, because I ate every 15'. I'd be fine at any time as long as I ate that often! But of course we don't. The solution was very simple: eat more fat and protein. The diabetes nurse said think of carbos as kindling and fat as a log. I needed to put more logs on the fire.

No, if you're doing well on a long ride you don't get depleted until the very end. That's the whole idea: pace yourself. You should always have enough glycogen for one more climb and then a good pace to the finish. If you're sitting in a ditch with colored lights flashing in your eyes, you've screwed up. That's happened to me.

Machka 

I didn't make the connection between eating and warding off the hallucinations, until it was suggested to me. I tried it, and it worked.

Now I am aware enough to realize I need to eat. Hallucinations are funny ... it's like most of your brain is right there in the present, completely aware of what's going on, but right in the middle of reality is a giant standing in the field to your right holding a movie camera and filming you. Part of your brain says, "WOW, a giant!! I've never seen one of those before!" and another part of your brain says, "What nonsense, you must be hallucinating. Eat something." And usually when I think that, the hallucination disappears.

What really gets me are the floating animals. I'm never sure if those are real or not. Not that the animals would actually be floating, but there could be real animals crossing the road, and my brain, the darkness, and my bicycle lights might combine to make the animals seem like they are floating. Or maybe they aren't there at all. I'm pretty sure the dragon I saw flying over me on my 600K last year might have been an owl and my lights and brain transformed it into a dragon. Or maybe there was nothing there at all.

2manybikes

I think that was the sag dragon. Did he offer to carry your bike and give you a ride?

Machka 

No he just flew off without saying anything. Didn't even look in my direction!

2manybikes

spokenword

One of my fonder sleep-deprived hallucinations involved eighteen wheeler tractor-trailer trucks morphing into Chinese style serpent dragons, their exhaust stacks becoming horns, their headlights becoming flaming eyes and their side running lights transforming into twinkling jewels encrusting their undulating, scaly hides.

... and when I say 'fond' I mean 'terrifying at the time, but mellowing out into awesome in the safe hindsight of memory.'