For many people, completing one marathon would be an achievement.
But Melanie Sturman has not only just run 10 marathons in 10 days for the fourth time, but has also clocked up her 200th marathon - and achieved 52 marathons in 52 weeks.
The 46-year-old, from Thetford, who started running six years ago on the advice of her doctor, believes she is only the second woman in the country to do the 10 marathons in 10 days challenge four times. She is also looking into whether she has earned a Guiness World Record by doing it in three years and 10 months, which could be the shortest period of time it has been done.
The Thetford Parkrun director said she did not plan on amassing such an impressive marathon record. 'I never thought I would do 200 marathons,' she said. 'I keep looking at my badge at home and thinking: 'Really?' I think this year it was about trying to see if I could improve my times.
'I started running at 40 because I was told I was overweight and that I had high blood pressure and needed to do something. So I thought I would try for the London Marathon.
'It was my fifth marathon and I saw a woman in her 40s or 50s presented with her 100 marathon top. I thought it was impressive and it spurred me on.'
Miss Sturman's next challenge is to complete the World Marathon Majors. She has already taken on London and Berlin and is hoping to apply for New York next year before doing Chicago, Boston and Tokyo.
Her 52 marathons in 52 weeks have seen Miss Sturman, a nurse who works for Norfolk County Council, travel around Britain and abroad.
In January she travelled to Florida where she took part in the Dopey Challenge - a 5km, 10km and half-marathon run which is finished off with the Walt Disney Marathon.
Miss Sturman said it was her favourite run because it was 'magic and such a laugh'.
She also completed the tough Snowdonia Marathon in October, which includes a climb to about 1,200ft.
And despite her achievements it does not appear Miss Sturman is going to start taking it easy.
'I want to work towards my 300th marathon before 2020 when I turn 50,'she said. 'Then I will get listed in the world rankings.
'I thought that would be a great 50th birthday present.'
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