When Eliud Kipchoge stepped off last summer’s Olympic marathon course with a sore back, the greatest of all time was declared yesterday’s man.

But five years on from his most recent appearance at the London Marathon, Kipchoge, 40, will return in April preparing to win again.

He says his Paris nightmare, a first failure to finish over 26.2 miles, was simply a bad day out rather than a sign of terminal decline. And he bristles at the mention of retirement, declaring in typical philosophical style that he will only stop “when the world becomes a running world.”

Kipchoge admits “a lot was running through my mind” after Paris and it felt “demoralising” to not finish an event he won in Rio and Tokyo.

But he went home, entered zen mode and realised: “You need to wake up, go again and push on every day.”

So he is building up to London with the tunnel vision that has brought world records, medals at four Olympics and 11 major marathon wins throughout more than two decades at the top.

“I still think I can compete,” he insists.

He is knuckling down to his familiar schedule – 130-mile weeks across 13 sessions, only Sunday afternoons off – and that workload certainly jars with the idea of a man considering retirement.

“I’m training like 10 years ago,” he says. “It still pushes me to the next level, to the finishing line.

“I don’t see any meaning in changing the training. I’m still following the programme, training as usual and I’m happy for it.”

Kipchoge will also happily share some wisdom with triathlon champion Alex Yee before the race.

Hometown hero Yee, making a surprise marathon debut, has previously said Kipchoge is his favourite runner.

And the Kenyan reckons he can both learn from and impart knowledge to Lewisham’s finest in a “pure discussion” about the bigger picture.

“I’d love to know him more,” Kipchoge adds. “The discussion will be about humanity, about the love of sport that is running. How are we going to sell the sport of running?”

At the peak of his success Kipchoge was a marketers’ dream, shifting shoes by the shipload through his pearls of wisdom.

Even now, with expectations dialed down, he talks about inspiring others as the prime reason to keep going.

“The fans,” he says when asked why he will return to London instead of touring the other big city marathons.

From most athletes such a response would produce an eye-roll.

For Kipchoge, however, it is a statement in keeping with that carefully cultivated image as savant of the roads.

“I’m really worried,” he says of the global obesity crisis at another point of this conversation.

And when the time to stop competing eventually arrives he will “go to cities to see these people because I want everyone to get the benefits of running, both physically and mentally.”

He promises to announce what’s next straight after London but it already looks like a choice between the World Championships in Tokyo or one of the autumn majors.

For the next 14 weeks, though, London is what “all my mind, my heart, my energy is on.”

The runner who has redefined what is possible almost sounds like a man determined to prove doubters wrong.

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