Grand Slam-winning former Wales rugby captain Ryan Jones will run a marathon in his garden on Saturday.
He is supporting a campaign to raise extra resources for the Swansea Bay University LHB charitable fund during the Covid-19 pandemic.
Newport-born Jones, 39, is currently the Welsh Rugby Union's performance director.
The ex-Ospreys forward has already substantially surpassed the £500 target on his Just Giving page.
Explaining his plans, Jones said: "Like many I am confined to my home and as this situation plays out before me, I am just amazed at the strength of the human spirit and the generosity of so many.
"Those giving of their time not because it's a job but because they care, those putting the risk to their own health to one side because they care.
"You truly are an inspiration and I just wanted to try and support you."
He estimates the run will require around 700 lengths of his garden.
"I don't think the view is going to be great," Jones told BBC Radio Wales breakfast.
"I'm just going to have a green length of hedge and grass to look at for the best part of five or six hours really with all the turns.
"The only luxury I have got is the toilets are clean and not far away on this run, which is different to your major events.
"I've got three young kids who are all under 10 who have made some signs and I'm sure they'll be cheering me on and joining in and the like as well."
Jones won 75 Wales caps, winning the Six Nations Grand Slam in 2005 and then again as captain in 2008 and 2012.
He held the record for the highest number of games as Wales skipper - 33 - until that was surpassed by Sam Warburton in 2015.
Jones made three appearances for the British and Irish Lions on their 2005 tour of New Zealand. He was also a late call-up for the Lions 2009 trip to South Africa, but arrived injured and did not play.
His playing career ended in 2014 on medical advice because of recurring shoulder injuries and in 2016 he was appointed the WRU's head of rugby participation. He took up his current role in 2019.
Jones, who lives in Swansea, said he will be posting updates throughout the challenge on his Instagram account.
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