Speaking before taking on the run, Flatt, who has undertaken countless fundraising challenges, said: “You can get so much joy out of life regardless of the challenges you may face.
“There’s so much love and friendship in this community. You’ve got to embrace life and just enjoy it.”
Jo Coker, from the MND Association, described the atmosphere as “absolutely electric”.
She said 541 runners raised funds for the charity.
“This was a little known disease five years ago,” she said.
“Rob [Burrow] made a huge difference to the awareness levels and there are people out there who are really carrying that forward.”
She said money raised not only went towards research and treatment but also to supporting families living with MND.
“Over £4m will go towards to help them with things like housing adaptations, equipment they might need but also for those around them.”
About 45,000 people have taken part in the marathon and a half marathon since the event began.
This year, about 5,000 runners are thought to have taken part, raising funds for various charities.