Seeings this Thread is dedicated to me, I'll contribute 'at will'.
Some people thrive on adrenaline, and just ride through the barrier to get their 'second wind'.
For me, this happens after about three hours. If I eat something, I delay the adrenaline and sink back into feelings of exhaustion.
After another three hours, I stuff my face with fat laden protein snacks ( Big Macs ) and cups of full milk Latte.
That keeps me going for another six hours. Then the whole thing repeats.
When the adrenaline hits on a calendar 200 and you feel like you're flying, when you arrive at the finish well ahead of everyone else, you get temped to shout out "I've won, I've won". The organiser and others present think you are a complete arsehole.