The fourth of Kevin Sinfield's seven ultramarathons in seven days to raise money and awareness for motor neurone disease (MND) research has started in Sheffield.
The rugby league legend set off from Bramall Lane stadium, the home of Sheffield United, at about 08:30 GMT, cheered on by supporters.
AdvertisementAdvertisementAdvertisementHe is expected to finish at the University of Sheffield's Institute for Translational Neuroscience (SITraN), which researches treatment for neurological disorders including MND.
On day three of the challenge in South Wales, Sinfield met the family of 14-year-old Kyle Sieniawski, who died last week after being diagnosed with MND in January.
As of 09:45, Sinfield's fundraising total had passed £650,000, with the 45-year-old setting a £777,000 target.
Sinfield's route around Sheffield will take him to Abbeydale, the home of Sheffield Collegiate Cricket Club and Sheffield RUFC, Sheffield Olympic Legacy Park, the English Institute of Sport and Hillsborough stadium.
AdvertisementAdvertisementAdvertisementHe is expected to finish at about 14:45.
Where to see Sinfield's challenge in Yorkshire
"I am particularly pleased to be finishing at SITraN to shine a spotlight on the incredible work of the researchers there and the work they are doing," said Sinfield, who is running in memory of his friend and former teammate Rob Burrow.
Burrow was diagnosed with MND in 2019 and died in June 2024.
Last month the Rob Burrow Centre for MND opened in Leeds in his name, dedicated entirely to MND care, research, education and holistic support.
The facility was paid for in part through Sinfield's fundraising, which now stands at more than £10m.
Sinfield's latest ultramarathon challenge sees him visiting many locations for the first time to reach out to more members of the MND community.
AdvertisementAdvertisementAdvertisementHe began his challenge in Bury St Edmunds in Suffolk on Monday, running to Ipswich, before taking on his second ultramarathon in Cork the following day.
Sinfield was back in the UK on Wednesday to complete an ultramarathon in Swansea.
He said he was feeling "good" on Thursday morning despite a "big bus journey last night".
On Friday, Sinfield will run from Workington to Whitehaven before heading to Dundee on day six.
The final day of Sinfield's 7 in 7 challenge will see him run from North Yorkshire to Leeds, finishing at Headingley Stadium, the home of Leeds Rhinos.
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Sinfield reveals latest MND fundraising challenge
Where to see Sinfield's challenge in Yorkshire