Why did I feel compelled to compete athletically (I use the word in its loosest sense)? I was shamed into it by the managers who report to me at Shelter. Each of them, be they short, tall or round (and believe me, they come in all shapes and sizes) had decided to do the Great North Run, leaving me with three choices, all of them equally unpalatable: do the run myself; do nothing; take part in a different event.
The first option seemed to me to be the worst: I was sure I couldn't run a half-marathon and, even if I could, I certainly didn't want to follow my staff home. The second indicated a lack of commitment to the sector I love. By default, I chose option three. As a trustee of Hope and Homes for Children, I had heard about plans for its annual triathlon and decided to take part. Admittedly, my swimming, cycling and running were all poor, but my logic was that it had to be better to share weakness across three disciplines than fail in one longer one.
With no minimum amount to raise but with most competitors coming from the City and raising four-figure sums, I set myself a target of £1,000.
I devised what I thought was a cunning strategy: target my closest friends and family and tell them I was seeking support from an elite group of 20 individuals to help me reach my £1,000 goal. The strategy worked. Eleven of them responded (55 per cent) with an average gift of £50 - they had done the maths. One did squeal, saying she felt more like part of a database cell than one of my nearest and dearest. I then broadened my focus to other friends and family, raising the target each time it was neared.
My first run lasted 19 minutes and almost two miles. I got home and collapsed to "are you back already?" Next up was the cycling. I borrowed a bike and started riding into work, which I found surprisingly enjoyable. I even took a swimming lesson, during which I was told that my breaststroke would be better than my splashy crawl and that I'd be just about good enough to join my 10-year-old daughter's swimming class.
It was one thing practising the three disciplines separately, but the transitions between them make all the difference, so I began cycling, flinging my bike down (as untidily as a Virgo can) and going off running.
My two-mile time increased by an appalling eight minutes, but I kept at it for two months, exercised almost every day and soon my times came down.
I even ran 10 kilometres and didn't feel too bad, something unthinkable at the outset. Then came the sting. Five days before the event, on a work trip to Glasgow, I went for a run without stretching properly. Sprinting along the Clyde in my England shirt, I pulled a hamstring and had to limp back. It was a huge blow because I could do no more training before the event.
At 5.50am, I was picked up by fellow triathlete and Hope and Homes for Children chair Matthew Bell, who was kindly giving me a lift to the starting line in St Albans. Matt was 10 minutes early, which was a shock because he is always late, but he hadn't been able to sleep.
A lovely surprise was waiting for me at the swimming pool: some friends had turned out to cheer me on. This reduced my swim time by at least a second, which was negated by my timing chip falling off my ankle after four lengths. I spent another four lengths looking for it.
After a quick change it was on to the cycling. It's amazing how fast you can go when there are no buses or traffic lights. Then it was the bit I was dreading: the run. To deaden the pain, I strapped up my leg and dosed myself on super-strength Nurofen, Tiger Balm and jelly babies.
I was determined to get round even if I had to walk. I managed to jog very slowly and overtook one person. The proper runners all zoomed past.
When I eventually made it across the finish line I felt fantastic.
The event had been immaculately organised in partnership with St James's Place, a long-time corporate supporter of Hope and Homes for Children, and was wrapped up with a prize-giving ceremony (nothing for me). This ended perfectly with an incredibly motivating talk by a St James's Place partner who had recently returned from a trip to Rwanda, where the money raised would go.
To all you out there making up excuses about being unfit or not having the time, they simply won't wash. Make a resolution to take part in a sponsored event this year - it'll change your life. Not only did I raise £1,800 for a fantastic cause, I'm also still exercising and am competing again this year.
Any reader feeling stuffed or guilty after Christmas is welcome to sponsor me at www.justgiving.com/madalan2007. And did I mention that Hope and Homes for Children's chief executive (in his mid-50s) and chair (aged 38) both took part? Which of the two finished first? The chief exec, of course. Don't they always?