Fans spot radio star Greg James battling through fourth triathlon challenge in Sheffield today

Greg has passed the half way mark of BBC Radio's Gregathlon for Sport Relief and is on day four in Sheffield. Not only will he be dealing with increasing agony from aching muscles with but tiredness will make everything that bit harder. Greg said: "We had the worst journey last night from Glasgow to Sheffield. What was supposed to be a four hour journey turned into seven, so I've only had 4 hours sleep. That's why the challenge has been harder than I thought, it's been exhausting travelling from city to city. It's been great having some guests come up and see me though, it'll be so nice having Grimmy and Example with me today. Even though my body is saying please stop, there is no way I'm giving in. I'm in the zone, even if my legs are not. I think they might still be in Belfast. I'm hanging by a thread. There are lots of people involved with this and we're all feeling it today. I really need everyone's help and support to get through the next two days." Visit sportrelief.com/Greg for more info.

Presenter and DJ Greg, from BBC Radio One, has signed up for five triathlons in five days as part of this year’s Sport Relief campaign.

Sheffield is one of the six cities chosen to host a flagship Sainsbury’s Sport Relief Games in March, where people can walk, cycle or swim to boost Comic Relief.

Greg will do his bit a month early - swimming a mile in Ponds Forge, running ten miles and cycling 45 mile.

His route also takes in Coal Aston and Dronfield.

Fans have taken to Twitter to send the star good luck messages on his fourth day of pain.

One wrote: “Passed @gregjames on my way to work, my car struggles with Sheffield hills, he’s doing amazingly well! #Gregathlon.”

Shannon Cooke added: “Sheffield has to be one of the hardest places to cycle. Stay safe @gregjames and show them hills who’s boss! #sportrelief #Gregathlon.”

And Jaye Taylor wrote: “What a pleasant surprise seeing @gregjames peddling up a #Sheffield hill towards me this morning! #GoGreg #Gregathlon @sportrelief #cycling.”

Before the challenge began Greg told The Star: “I want this to be one of those challenges no one following it would want to do.

“It needs to be genuinely horrible for me so that people buy into it and donate their hard earned money to this incredible cause.”

But this morning he shared a picture of himself being helped up off the road on Twitter:

He wrote: “Not an ideal start to the Sheffield cycle. My minnnnndds telling me yes, but my body, my body’s telling me NO.”

“Need your help to dig deep. Text GREG to 70703 to give £3 to @sportrelief.”

Yesterday the presenter struggled in the freezing River Clyde, in Glasgow. Today he will be joined by fellow presenter Nick Grimshaw and musician Example.

This morning he said: “We had the worst journey last night from Glasgow to Sheffield. What was supposed to be a four hour journey turned into seven, so I’ve only had four hours sleep. That’s why the challenge has been harder than I thought, it’s been exhausting travelling from city to city.

“It’s been great having some guests come up and see me though, it’ll be so nice having Grimmy and Example with me today. Even though my body is saying please stop, there is no way I’m giving in. I’m in the zone, even if my legs are not. I think they might still be in Belfast. I’m hanging by a thread. There are lots of people involved with this and we’re all feeling it today.

“I really need everyone’s help and support to get through the next two days.”

To track Greg’s route throughout the day visit http://www.sportrelief.com/whats-going-on/greg-james-gregathlon/sheffield#gs-location