The run takes around 18 months to organise, said Nova.

Around 80,000 people applied for the 50,000 available places in Sunday's race, said organisers Nova.

The company also said the latest race will be the safest and best-organised yet after a detailed review into the death of four runners in 2005.

But Nova spokesman David Hart said each runner is ultimately responsible for ensuring they have trained adequately.

He said: "We've had an intensely detailed review process following last year's race. Most changes won't be noticed by runners, but we've made a few alterations at the start.

"We've also bolstered up medical attention to make sure we have a very well-organised and safe race.

"Ultimately though, it has to be the responsibility of the individual. Our message over the course of the last few months is to respect the challenge. It's a long, long way - significant physical exercise and you do really need to be prepared."

Hundreds of celebrities and professional runners will take part in the race, which will be started by England boss and former Middlesbrough manager Steve McClaren.

Rail operator GNER will provide extra trains on the East Coast mainline for people travelling to the event.