On Sunday more than 40,000 people took part in the London Marathon, with Prince Harry and the Duke and Duchess of Cambridge cheering the runners on.
Among the runners was Matthew Rees, who has been praised online for helping a fellow athlete when he saw him struggling, just metres from the finishing line.
Prince William and Prince Harry applauded as Rees stopped to help David Wyeth on the Mall, just outside Buckingham Palace.
Wyeth was raising money for the Isabel Hospice in memory of his late uncle.
Rees, from Swansea, told the Press Association that he went to cheer on Wyeth, picked him up, and said, "Come on, we can do this."
People were moved by the selfless sporting gesture.