Olympic silver medalist Sonia O’Sullivan managed to overtake more than 25,000 runners before finishing Sunday’s BUPA Great North Run, despite being the very last to start.

Sonia was running in aid of UK blood cancer charity Leukaemia & Lymphoma Research and is a regular runner with the charity’s TV Times celebrity running team.

She was also fundraising for the Children’s Leukaemia Association at Cork’s Mercy University Hospital in Ireland.

Sonia competed alongside hundreds of other members of Leukaemia & Lymphoma Research’s ‘Banana Army’ running team, so called because of their bright yellow t-shirts. The Banana Army is sponsored by TV Times and Adidas.

In an unusual fundraising challenge, the Irish multi-medal winning athlete asked people to donate money to her chosen charities for every runner she overtook during the 13.1-mile race.

Charity boss Cathy Gilman, of Leukaemia & Lymphoma Research, said: “To overtake so many runners in a packed field is absolutely incredible. To witness her passing 25,313 runners in Leukaemia & Lymphoma Research’s bright yellow t-shirt was amazing!

“The fundraising challenge was a great idea and has really helped raise awareness and money for our life-saving research into blood cancers, including leukaemia, lymphoma and myeloma.”

People can still sponsor Sonia O’Sullivan’s achievement at www.justgiving.com/fromfronttoback