Sir Mo Farah warned of 'brutal' marathons

Great Britain's Mo Farah on the floor after winning the men's elite race during the Great North Run in Newcastle Photo by Richard Sellers/PA Images via Getty Images

Great Britain runner Callum Hawkins has warned Sir Mo Farah to be ready for the brutal marathon.

Scotland's Hawkins is relishing the chance to face four-time Olympic champion Farah now he is focusing on road racing.

Hawkins beat Farah at the Great Edinburgh Cross Country in January, finishing second ahead of Farah in seventh.

And he knows it will be a culture shock for Farah with the pair set to face each other at the The Big Half, London's new half marathon, in March.

"The marathon is a completely different event to the track, just because of how long it is and there are other athletes who come into it," said Hawkins, who came fourth at the World Championships this year.

"The impact on the legs is a huge factor, rather than what your heart and lungs can do. People underestimate what that can do.

"For me, at the end of the marathon, it feels like someone has been punching my quads all day.

"It's a brutal event because you can catch a cold a week or two before it and that's months of training gone.

"It's not like you can do another one, especially if you start it and it doesn't go well. It's a gruelling and tough mental challenge."

Farah has been careful in his predictions -- stating he is not expecting to challenge for titles yet and will only compete for Team GB at the Tokyo Olympics in 2020 if he can make the podium.

The Big Half in March will be Hawkins' final race before the Commonwealth Games in Australia next year.

He said: "It will be good to race Mo when he's at full fitness. The last time, at the Edinburgh Cross, he was nowhere near full fitness so I don't really count it as a win. Hopefully we'll both be at full fitness and it'll be some battle.

"I'm really impressed by the concept of The Big Half. Running is probably the most accessible sport in the world and this is a fantastic way of encouraging more people from all backgrounds to give it a go."