A FITNESS fanatic is gearing up to take on the 'world's toughest footrace' through Greece.

Owner of Evolve Health and Fitness, in Bicester, John Stocker says the nerves are kicking in as he faces one of his most gruelling races - the Spartathlon.

The daredevil will take on the153-mile ultrmarathon from Friday and has just 36 hours to complete the challenge.

He said: "When I put the application in to be part of the British team I felt really positive. I am slowly starting to feel really nervous now, as it is getting closer.

"I have done more than the 153 miles before but every race is different and brings with it different challenges. This one will be the heat and in the ultra world it is the race you look at and think wow.

The dad-of-three will be one of just 25 other British runners to take on the Spartathlon – known as the toughest footrace in the world.

The British team’s 2018 captain Paul Ali said: “We have a very strong team this year that includes 11 runners who gained automatic qualification to the race thanks to their past results."

He added that they're are confident in hoping for a British win.

Mr Stocker will have to battle extreme heat, traffic, strict cut-off times and a mammoth 1,000m mountain climb at the 100-mile mark.

As part of his training Mr Stocker has been to Thailand on a family holiday, although clocking up 100 miles over two weeks to help train in heat.

The 38-year-old will join a field of 390 athletes taking on the Olympian feat from across the world journeying from the Acropolis in Athens to the statue of King Leonidas in Sparta.

The race follows in the footsteps of Athenian messenger Pheidippides, who ran the distance in advance of the 490BC Battle of Marathon to ask for Spartan help against invading Persian forces.

Along the way there will be 75 check points in which every runner has to meet cut-off times, or face joining the ‘death bus’ and are not allowed to finish.

It won’t be the first extreme event Mr Stocker has taken part in after completely scores of marathons and frightful feats.

Mr Stocker, who opened the Bicester Gym in Murdock Road in 2011, tackled the impressive Spine run last year - a 268 mile race across the Pennine Way.

The Spartathlon will begin at 7am on Friday.