Tigist Assefa wears Adizero Adios Pro Evo 1 running shoe from Adidas in record-breaking Berlin Marathon win

The 29-year-old shocked the globe when she steamed across the finish line at the Berlin Marathon more than two minutes quicker than any woman has before in a blistering time of 2:11:53.

It was a moment that not even the most sophisticated of race forecasters had foreshadowed, with all eyes having been firmly on Kenya’s Eliud Kipchoge, who was pegged to blast the men’s world record.

So when Ethiopia’s Assefa charged through Brandenburg Gate with what seemed like plenty more in the tank, all anyone could do was watch in awe.

But, since her historic win, an incredible detail has come to light – the shoes that sped her around the course were a yet-to-be released so-called “supershoe” worth an eye watering $777.

They were the Adizero Adios Pro Evo 1s which have been described as marking “a new era of racing shoe – designed to revolutionise running economy and set new marathon records”.

While the price tag alone was enough to send running enthusiasts into a spiral, an even more alarming detail has been uncovered.

Charlotte Heidmann, the senior global product manager at Adidas, told Runners World that purchasing the shoe came with an important disclaimer.

The shoe has apparently been made only for “one race – so one marathon – plus familiarisation time”.

That would make it just over $18 a kilometre.

Assefa, based on her marathon time, would have spent that in slightly more than three minutes.

The eye watering price and odd disclaimer has sparked backlash among runners, with many pointing out it went against Adidas’ attempt to market itself as a sustainable brand.

“Don’t champion as a sustainable shoe innovator ending plastic waste and make a 500 ‘designed for one race’ shoe,” one person commented on Adidas’ Instagram post promoting the new shoe.

Another user commented that while the “sustainability values of Adidas are 2nd to none”, and their shoes have made “immense progress in improving use of recycled material”, this new shoe doesn’t seem to fit in with those values.

“How do these principles align when you design a shoe, as great as it may be, to last a single race … has Adidas Running forsaken its key sustainability principles in exchange for glory?” the commenter, a self-described marathon runner, asked.

Yet another person said that while Adidas was responding to comments about the speed of the shoe, they hadn’t been responding to sustainability comments, to which Adidas replied:

“The shoe’s upper is made from recycled nylon and the midsole foam consists of 40% bio-based castor oil. This is the lightest performance running shoe we’ve ever created and is a specialist innovation product, designed for experienced and advanced runners and optimised for one race.”

Regardless of the shoe, Assefa’s incredible athleticism was impossible to dispute.

Having only raced her first marathon last year, finishing in 2:34:01 in Riyadh, Saudi Arabia, she said it was her perseverance that shot her over the line in world-record time.

“I think this is the result of hard work over the last year,” she said after the race.

She qualified for Berlin, an Abbott World Marathon Major, in the same race last year when she finished first in a time of 2:15:37, which at that stage was the third fastest ever.

Assefa represented Ethiopia at the Rio Olympics in 2016 in the 800 metres, before switching to roads in 2018.

Making history in such a profound way on the weekend was not exactly her plan, she said.

“I wanted to break the record but that was not expected.”

brooke.rolfe@news.com.au