A week.

I was in my teens and had no commitments at the time and just spontaneously decided not to eat or sleep for a few days - which I later decided would be a week. At the time, I had no idea of the world record for this or I probably would have tried for that - although, obviously, I was not supervised or anything.

The afternoons from the second day onwards were the worst - when I felt pretty lousy - but otherwise I was running on serotonin and was pretty much on a natural high for most the duration.

At the end, I cycled 12 miles during which one of my feet cramped and left me jabbing at the pedal as it went past, but I did it ok.

I slept extremely well when I finally did, but I took some while to get back into the whole eating thing again.

There is no way in hell that I could do anything like that now.