Rugby star Jonathan Davies and his wife Helen joined the Great North Run on Sunday, to raise more than £300,000 for a cancer unit.
The couple had been training for months
A record £364,000 was pledged in online sponsorship for the couple's 13-mile run.
The couple joined thousands more charity runners for the half-marathon on Tyneside.
The money raised will allow the first cancer unit for teenagers to be built in Wales within two years.
The ex-Wales rugby player and Great Britain rugby league international was delighted by the response to the sponsorship appeal.
It was his first half-marathon for 20 years. Before the race, he said he would just be keen to finish without any injuries.
"Helen and I have both been out running. The training's gone okay but Helen's done more, " admitted Davies.
A massive £250,000 of the sponsorship is coming from the sports charity, The Wooden Sport Society.
Davies said he was very grateful to all the businesses and individuals who had also pledged their money.
"It just shows that when it comes to giving for causes like this you can rely on the people of Wales," he said.
The Teenage Cancer Unit is part of the Noah's Ark Appeal, which is behind the first Children's Hospital for Wales, in Cardiff.
The £300,000 is the final chunk of the £2.2m needed to ensure that the building of the unit goes ahead.
It will be the biggest of its kind in the UK and cater for 200 teenagers a year.
Noah's Ark Appeal director, Suzanne Mainwaring, said most of the funding had been provided by a UK charity.
She said the Great North Run fundraising project with Jonathan Davies and his wife had been one of the biggest individual efforts backing their campaign.
"Jonathan has been one big supporter from the early days," she said.
The sportsman was helping the appeal with their "Get Fit, Get Healthy, Get Giving" campaign to take action against preventable diseases like heart disease, diabetes and many forms of cancer, she added.
The first phase of the £10m children's hospital opened in time for St David's Day this year.
The Welsh Assembly Government has put aside £40m for the second phase of the project - which includes six large operating theatres and a large outpatient department - but no date has been set for work on that to start.