When I announced at New Year 2013 that I was giving up smoking as the first step in training for the Berlin Marathon my family smiled kindly and said "well done - you go for it, love".
But I don't think they thought I would actually do it.
For the first 7 days in January, I allowed myself to eat and drink whatever I wanted and in whatever quantities I wanted. I'd been a smoker for 29 years and not smoking was leaving a huge void that somehow needed filling.
Then I remembered the last time I gave up smoking.
In the space of 2 years, I gained 3 stone. In the four years after that another 2. Clearly, there were other factors in play too, but still. I had managed to lose a little of that by taking up smoking again, but in January this year, I was still approaching 14 stone. There was no way I could afford to gain even a stone.
So on January 10th, I launched the second stage of my Marathon training plan. I gave up drinking and I gave up cake. And sugar generally. And crisps. And whatever other rubbish was playing too big a part in my diet.
When friends asked how my training was going and I said "great, I've given up cake", they thought I was nuts, told me well done, and talked amongst themselves about how I was never going to be able to run a Marathon.
But what did they know?
Without fags, without sugar, without booze, I had a powerhouse of energy coming alive inside me.
Enough to power 10km brisk countryside walks. Probably enough to run, but I was too scared to run.
Scared of not being able to do it, scared of what I'd look like, scared of hurting myself. Scared.
But I stayed off the fags, lost a stone and kept my drinking to a minimum. By March, I really had no option but to start running. Thank goodness for the Couch 2 5km app.
The groundsmen at the football pitch opposite my house got quickly used to the sight of me plodding my ass round and round in circles. And I got used to feeling like an idiot.
I knew deep down I was going to make it in Berlin. I had such a clear picture of myself smiling in elation crossing the finishing line. I had made a sponsorship commitment to Save the Children and to those that had sponsored me.
There was no way I was going to fail.
In the end, it took me 5 hours and 58 minutes. I smiled the whole way, apart from the last 2 km.
So now I'm going to have to do it all again, to live that vision of smiling across the line.
This time, I'm going to Amsterdam.