Back in February 2015, my friend Luke Blake was preparing to begin his 250-mile, 18-month challenge with the Silverstone Half Marathon. I wanted to offer him moral support - so with barely four weeks of training, from nothing, we took on the Formula One track together.

I was three minutes 13 seconds off my 1hr50min target - which was still a personal best. But the really satisfying part, what stuck with me, was how much support my chosen cause received.

As I wrote back in March 2015, I have seen the effects of Alzheimer's disease both first hand and through my work as a sports journalist; a number of former footballers' families have been left to deal with dementia.

But what struck me through fundraising for Silverstone, was the sheer scale of people the disease has affected and the battle those families and friends face - one that runs for years, not days or weeks.

So from fundraising, talking to people and the actual challenge of the run, I've decided to do it all over again - but on a completely different level...

Since high school, I have always wanted to run the London Marathon. Luke got the chance last year as part of his challenge - so in 2016, I'm giving it a go.

Just to clarify: I've only ever ran two half-marathons in my life (and now three as of November 2015), and had never clocked more than 13.1 miles in a single outing. My training for London has now taken that up to 17 miles. Just. 

As I mentioned just then, I took on November's City of Norwich Half Marathon - as I did back in 2008 - to help get me up to speed and through shin splints plus injury-hit training, I finally clocked that first time under 1:50.

But now it's all about London. I have to say the thought of doing double that distance, in one go and at a pace that might take me anywhere close to four hours, gives me a tight chest.

So yes, I have always wanted to run the London Marathon. But it's something I've been inspired to do by the chance to earn a relatively substantial amount of money for Alzheimer's Research UK. Certainly the fundraising target feels just as daunting as 26.2 miles.

Back in March 2015, we smashed the modest aim of £350. Just like I said before that run, all I hope for from London is to raise all the money we can and either help make life a little more bearable for those currently affected, or add to what's being done to treat those afflicted in future.

That will keep me going when my body asks me what the hell I'm doing. I hope it also inspires you to donate to the cause. Thank you!

Now for the footnote...

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