i expect the people at the Guinness book of records had to set a standard nurse uniform
I also expect they also have a standard fireman's uniform and a standard rhinoceros outfit
they do have a point, it's a joke category, as is chef with big hat and pot. Why they even want a Guinness World Record category of Fastest Nurse in Carry On Uniform, I don't know, but if you want to win it, those are the rules.
I don't think it's any kind of official London marathon rule, it's just Guinness.
Someone went round dressed as Big Ben simply to get the record for the fastest time by someone dressed as a building.
It was a very impressive time given the weight of the costume but who on earth cares about this sort of record? The achievement lies elsewhere.
Guinness has stated what the nurse costume must consist of, and therefore contestants should adhere to this dress-code, if you will. However, I agree, it is really dated and should be changed (unless it is in a 'joke' category as someone suggested). And perhaps this nurse's action will result in a change, but as it stands now she did not qualify to win.
she wasn't denied the record, Tilly, she was told the criteria in advance and chose not to meet them. I don't blame her, but there's no scope for making your own rules to win other people's awards.