He normally does these things in either teams of 4 or 6. Mostly a team of 4.
They normally just do one lap each although during the middle of the night the strongest couple on the team might do a two lap stint so people can sleep for longer.
Sometimes he is in a mixed team but mostly it is a mens team. They've won or placed in a lot of the enduro races in their category over the last half a dozen years.
He's never done any of them solo. The only solo MTB race he really does is the Half Highland Fling where he has won the Super Masters a couple of times.
I am hoping when I am 50+ some sort of gene kicks in and I get the fitness bug that he has. I sure don't have it now...