Every Englishman grows up with the same dream: striding out at Lord's, bat under the arm, and scoring a century in front of a packed house.

Raise the bat to the pavilion.

Get the name on the honours board.

Immortality.

I have now made peace with the fact that this is not going to happen with a bat in my hand.

So on Monday 28th September, I'm getting my hundred a different way - 100 laps of the Lord's outfield for Alzheimer's Society.

That's 50km. More than a full marathon. Around the most famous cricket ground on Earth, a hundred times, until my legs file for divorce.

And here's the part I've actually trained for: after lap 100, I'll walk back into the pavilion and into the famous Long Room.

But I won't be raising a bat. I'll be raising a beer. Century complete.

Some heroes lift willow. I'll lift a pint. Frame it, put it on the board, I've earned my spot.

The serious bit, because there is one: this is part of Sport United Against Dementia, bringing the sporting world together to fund research and frontline support. Dementia is the UK's biggest killer - nearly a million people living with it, and countless families working out how to cope, often without the help they need. Sport is very good at uniting people. And this is exactly that, pointed at something that matters.

My target is £3,000. What it does:

£27 funds an hour on the Dementia Support Line, answering a family in crisis

£56 helps a Dementia Adviser guide someone through diagnosis

£250 keeps frontline support running for people with nowhere else to turn

So: please sponsor me to walk in circles until I can barely stand, all for the honour of raising a beer in the Long Room.

Every donation gets me closer - and if you're a UK taxpayer, tick the Gift Aid box and the taxman adds 25% for free.

Lap counts and photographic evidence of my on field decline to follow. My name's going on the board one way or another.