Jon Webb is one of the fittest guys I’ve ridden with. On 22/23 June he decided to do the 24hr Red Bull Mountain Mayhem solo (as opposed to the usual team of four or more). That’s 24 hours non-stop mountain biking.
The tiredness was beginning to totally consume me, on one of the steady uphills I closed my eyes for a second of relief, only to find myself lying on the ground when I opened them again.
Jon provides more harrowing details.