Amanda Chalmers was born with cystic fibrosis and will run the Brighton Marathon less than two years after undergoing a double lung transplant.
The 26-year-old University of Brighton graduate could hardly walk up the stairs before her life-saving operation in September 2012. She'll be raising money for the Cystic Fibrosis Trust.
We caught up with her while training in nearby Preston Park. You can sponsor her here.
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