The former rugby player – who previously ran 101 miles in 24 hours – is intending to run seven ultra marathons in seven days, meaning he’ll run more than 300 miles in one week.
He hoped to raise £77,777, (Burrow wore the number seven on his jersey), to support Burrow and his family, as well as to raise money for the Motor Neurone Disease Association (MNDA).
But supporters raised £2,744,615 – more than £2.5 million more than the initial target.
Sinfield then completed the 101-mile challenge in 2021. He intended to raise £100,000, but this campaign also ended up raising more than £2 million.
Now, he’s taking on this latest challenge following the diagnoses of former Scottish rugby-union player Doddie Weir and ex-Bradford City footballer Stephen Darby.
The money Sinfield raises from the challenge will go towards the new £5 million Rob Burrow Motor Neurone Disease Care Centre in Leeds.
The challenge will begin in Edinburgh before taking Sinfield to Melrose, Newcastle, Middlesbrough, York, Leeds, and Bradford, and will end at the Rugby League World Cup final at Old Trafford, in Manchester, with Sinfield set to run into the stadium at half-time.
Former Gloucester rugby player Ed Slater, who was recently diagnosed with MND at the age of 34, appeared on BBC Breakfast alongside Sinfield, Burrow, and Weir, to launch the challenge.
Speaking to the BBC, Sinfield said: “I want the MND community, I want Rob, I want Doddie, I want Stephen, and I want Ed to know that there are people out there who are willing to go to some dark places for them — I’m certainly willing to do that.
“A part of me does enjoy going there, does enjoy that challenge. When you finish your playing career, you are still looking for fulfilment and these challenges have certainly helped me along with that.
“I know it’s going to be pretty brutal, training has been tough, but it will be worth it in the end.”