Image copyright Eric Tolentino Image caption Jessica Anderson called the guidelines "sexist" and "outdated", leading to a review of the rules

Officials have backtracked over their refusal to award a world record to a woman running the fastest marathon in a nurse's uniform.

Jessica Anderson was originally told her attempt would not be considered because she wasn't wearing a dress.

The 22-year-old said the decision was "sexist".

Guinness World Records reviewed its guidelines and found the rules "reflected a stereotype we do not in any way wish to perpetuate."

No scrubs

Jess is a senior sister at the Royal London Hospital.

Her work in an acute medical admissions ward is fast-paced and she wears scrubs to work every day.

So when she decided to challenge the title for the fastest woman to run a marathon in a nurse uniform, she sent Guinness World Records a photo.

She was told that her actual uniform did not meet its criteria for a nurse's uniform, which also involved a pinafore and cap, but tights were optional.

Jess ran the race anyway, completing the course in three hours, eight minutes and 54 seconds, which was fast enough to beat the record.

Image copyright Getty Images Image caption Thousands of people run in fancy dress every year

"I would be quite happy if they changed it [the rules] in the future or acknowledged that it's sexist and it's not really how we want the profession to be represented," Jess told Newsbeat after finishing the race.

That prompted a review from Guinness World Records, saying "inclusiveness and respect" were values it holds "extremely dear".

Then on Tuesday, a statement confirming Jess would be given the new record.

"I want to take this opportunity to reassure everybody concerned that Guinness World Records is absolutely committed to ensuring we uphold the highest standards of equality and inclusiveness.

"Therefore, we unreservedly apologise and accept full responsibility for the mishandling of Jessica Anderson's application."

'I've never worn a dress'

Before the decision was reversed, the story prompted nurses to tweet selfies of themselves, with very few dresses on show, using the hashtag #WhatNursesWear.

Some pointed out that certain roles don't require any kind of uniform.

And male nurses argued that dresses aren't really their thing.

Even the most senior nurse in England got involved.

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