Adidas seems to be ready to look its eternal rival in the eye Nike, in the race for the best long distance shoes.
On September 5, Kenyan runner Peres Jepchirchir set a new world record in a marathon, completing a 21,1km course in Prague in 65 minutes and 34 seconds. It was 37 seconds faster than the previous best time - completing each kilometer in about three minutes and six seconds.
As in the most recent long-distance world record, Jepchirchir wore a pair of fluorescent sneakers. But unlike the rest of the records, the shoes were created by adidas and not by Nike's rival. The American company has dominated a record in distance racing since 2017, when it released the first sneakers containing plates from carbon fiber that help people run more efficiently.
Now adidas comes to the fore with the model Adizero Adios Pro. For the past two years, about 50 adidas people have been working at Adios Pro. This particular model is a performance-based running shoe designed for racing and long-distance running.
It is the first real answer of the company towards Nike and is sold today with a price that reaches 184 euros. Unlike the vast majority of top running shoes, it does not include a full length carbon fiber plate. "We have seen the sport of marathon change and many product innovations take place," said Sam Handy, vice president planning of adidas. "But of course we do not launch products until they are ready."
Since Nike launched its first shoe of this type called the Vaporfly 4%, the rest manufacturers imitate the technology of carbon fiber level. The brands Rival Saucony, On, Brooks, Hoka One One, Asics have released their own racing shoes that include the same plates.
However, adidas has done something different with the Adios Pro. A series of curved carbon rods run through the entire shoe, which are wedged between two pieces of Lightstrike Pro foam.
"The origin of the rod is based on trying to reflect the metatarsal bones of the foot," says Handy. The rods are located under each bone in the foot and are curved to follow the shape of the foot, while they have been shaped to give the maximum possible energy efficiency when combined with the foam and other parts of the shoe. The company tried "hundreds" of different prototypes of the shoe with rods of different lengths, placing them differently and at different levels of rigidity.
Handy says the company also experimented with full-length carbon fiber plates - some of its other shoes use them - but eventually the rods with carbon was the best choice.
While independent studies have confirmed that Nike's Vaporfly range makes runners more efficient, we do not know the exact reason why this happens. The combination of carbon fiber board and ZoomX foam contributes to the overall performance increase, but none of them individually can be selected as the feature that makes the difference. To understand exactly why shoes are more effective would require controlled scientific studies where the shoes would be tested with and without carbon fiber plates (and plates made of other materials) to see where their high performance comes from.
Handy says a carbon fiber plate is not necessarily required to increase the performance of Shoes for running. Instead, it's all about the elements of a shoe. Each individual element can bring small advantages to the effectiveness of a shoe.
What matters is how quickly the foam in the shoe will break down and the stiffness added with the foam. "Everything is connected," says Alberto Uncini Manganelli, general manager of Adidas. "All the parts of a shoe work together and must work in sync. When you change one parameter, you have to adjust the other to get the best out of it performance. "
While sports companies can raise millions to create the most efficient shoes, there is another key element that plays an important role: the runner who wears them. To date, only professional athletes funded by the sports company have been trained and assisted in the development of the shoe. In the Jepchirchir world record in Prague, half the marathon included runners wearing adidas.
The number of records made with carbon fiber shoes has forced World Athletics to introduce new shoe rules in January this year - and the body continues to explore their impact on the sport.
Some critics say that high-performance shoes are a form of technological doping and that the records set by their use should be reduced. In some cases the athletes they wanted to separate their performance from the capabilities of their shoes. This is not the case with Jepchirchir, either, as it set a world record last week, acknowledging that technology has helped it. "I was exhausted for the last five kilometers," he said, "but the new shoes helped me set a new record."