Sorry... I never noticed that this thread got resurrected (sp?).
Merton, I'm not sure where the term comes from, but often after a maximal effort, you have no strength, energy, or will to continue at any significant level of effort. There's an anaerobic effort, which taken to extreme, will cost you far more in recovery time than you gained by the effort, but we're still talking seconds and minutes. When you "blow", it's like you've popped he balloon, and try as you might, it ain't gonna hold air no more 'til you fix it.
I'm not sure I completely buy hacker44240's explanation. I don't think the effort was long enough to use up glycogen stores. But I'm sure that's a significant part of it. And what do I know, anyway? I suspect there may be a central nervous system component, too. In any case, I appreciate the input.
Recovery depends... the situation I was describing, you're done for the day, so to speak. You can eat, etc., but you still won't be able to work hard enough to even get your heart rate up much. Time off the bike is the only real solution.
If you have to keep riding, do what you KNOW you should do. When I've gotten into a serious bonked state, my judgement goes right out the window. So I have to disregard my judgement, and do what I know I should do. Get calories and fluid. Drink the right stuff, eat the right stuff, and get off the bike until my senses start to return.