The event, the first by its new organisers, has been postponed until October because of the global pandemic, so 57-year-old keen runner Graham Merfield had to think creatively.
Under the rules of the island’s lockdown people are allowed to leave their homes for up to two hours a day in order to exercise.
Despite being an ultra runner, Mr Merfield knew he had no chance of being the second person in the world to break the two hour barrier for the marathon.
He proved his versatility by adapting the course and just running around his garden.
Mr Merfield was also raising money for the charity Medecins Sans Frontiers, to support its work around the world in battling the coronavirus.
The unusual course was completed in a time of 4 hours 21 minutes, which was longer than his normal pace because of the sharp changes in direction.
The makeshift finish line was fittingly some toilet roll.
Speaking after his feat, and with sore feet, knees, legs and shoulders, he said it was an enjoyable experience.
‘It was great actually, surprisingly less boring than I thought it would be.
‘I set up a course with quite a technical section going up a bank so it had quite a bit of climbing, I do ultra running and I run on the cliffs a lot so I like running up hills, but I had a nice course and Alison, my wife, was around to chat to on every lap, I had some music to listen to, I don’t normally run with music but I had a party list playing so every time I went past I heard that, so the time passed surprisingly quickly.’
Mr Merfield used a special watch with GPS and the runners app Strava to monitor his distance, which was around 130 laps of his garden and included 3,737 feet of elevation.
At the 18-mile mark his wife, who was supporting him with peanut butter sandwiches, hydration fluids and cheers, informed him that he had passed the £1,000 fundraising mark, so that was a great motivator.
Mr Merfield said it was the Clap for Carers that prompted him to attempt the challenge.
‘On Thursday night I went out into the garden to do the Clap for Carers, and I looked up at the stars and felt I needed to do a bit more, so on Friday morning I set up a Gofundme site and I thought Medecins Sans Frontiers was a good cause to back because they work globally and they’re doing a lot of work to help with the pandemic.
‘Different times and constraints force you to think differently and do things differently, and I would never ever have considered running a marathon in the garden before, it just seems ridiculous, but we live in different times and we have constraints on how long we can go out for.
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