The Prince and Princess of Wales made a surprise visit to support rugby league star Sir Kevin Sinfield, on the third day of his endurance challenge to raise funds for Motor Neurone Disease (MND) charities.
"What you're doing is so inspiring – the unity that you're building," Catherine told Sir Kevin.
Sir Kevin is aiming to complete seven ultra marathons in seven days, running between Hull and Manchester, in a challenge inspired by his former teammate Rob Burrow, who died from MND in 2024.
The rugby star's gruelling mission will end on Saturday at Old Trafford in Manchester, when Sir Kevin arrives ahead of the Super League Grand Final.
"Make sure you hold yourself together for another few days," Prince William told him.
Sir Kevin replied that he had been dreaming of an ice bath all day.
Since his first challenge in 2020, Sir Kevin has raised more than £11m for MND causes - and Prince William and Catherine made a private donation to the charity effort.
Before meeting Sir Kevin, the royal couple talked to families facing the impact of MND and heard how fundraising projects had helped them.
Earlier on Tuesday, Prince William and Catherine visited the home ground of Rob Burrow's rugby league team, Leeds Rhinos, and met some young players.
The royal visitors heard how the club's charitable foundation was working to help health, education and well-being projects in the Leeds area.
Jamie Jones-Buchanan, a former teammate of Rob Burrow, described the team's ethos in good and bad times: "We went through success and adversity, but we always came out on the other side together."
Prince William and Catherine have previously supported Sir Kevin's efforts for MND charities - and the prince had presented Sir Kevin and Rob Burrow with their CBEs at the Leeds Rhinos ground in Headingley in January 2024.
Rob Burrow died in June that year, aged 41, with Prince William among those paying tribute.
This was the second royal endorsement this week for Sir Kevin's charity run - with Princess Anne having shown her support for him on Monday at the University of York.
Although Princess Anne observed that the term "fun run" was a contradiction in terms.
"I can run but I don't do it for fun. I'm past that stage," she told Sir Kevin.
The knighthood awarded to Sir Kevin this year was among the first for a rugby league player.
There had been accusations that the honours system had been ignoring rugby league out of snobbishness.
But in June 2025, Sir Billy Boston became a rugby league knight - the first in the sport's 130-year history.
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