Factbox: Nike's Vaporfly running shoes and tumbling records

LONDON (Reuters) - World Athletics is set to announce the findings of a review of technology in road and track shoes by the end of January, and it is expected to change its rules in light of tumbling times recorded by athletes using Nike’s Vaporfly brand.

FILE PHOTO: Kenya's Eliud Kipchoge, the marathon world record holder, runs wearing Nike Vaporfly shoes with his pacemakers during his attempt to run a marathon in under two hours in Vienna, Austria, October 12, 2019. REUTERS/Leonhard Foeger

Following are some facts on the shoe and how athletes using it are breaking records:

- The Zoom Vaporfly shoes first came to prominence in 2016 and were worn by the first three finishers in the Rio Olympic men’s marathon. Nike have developed various versions since.

- Eliud Kipchoge, wearing a prototype Nike AlphaFly, became the first man to break two hours for the marathon in Vienna last year, albeit in an unofficial race.

- The Kenyan also wore a version of the shoes when he set the official world record of 2:01.39. Kipchoge’s 78-second improvement on the existing record was the largest improvement in over 50 years.

- His compatriot Brigid Kosgei beat Paula Radcliffe’s world marathon record in October in the latest version of the shoes, reducing the mark by 81 seconds to (2:14.4).

- Dutchwoman Sifan Hassan took double gold at the World Championships in Doha in September, when she won the 1,500m and 10,000m in a track spike version of the shoe.

- Last December Uganda’s Joshua Cheptegei broke the 10-year-old 10km road world record in Valencia by six seconds. The top five at the event all wore a version of Nike’s Zoom Vaporfly 4%.

- That record lasted only six weeks as 20-year-old Kenyan Rhonex Kipruto took a further 14 seconds off it. He was not wearing Nike shoes but a prototype carbon-insoled Adidas shoe.

- Japan’s Mariko Yugeta, wearing Vaporfly shoes, became the first woman aged 60 or over to break three hours when she ran 2:59:15 - more than three minutes better than the previous W60 record set by Claudine Marchadier of France in 2007.

- Analysis published by The New York Times showed runners wearing a version of Nike’s Zoom Vaporfly 4% or ZoomX Vaporfly Next% ran 4-5% faster than those who were wearing average shoes, and 2-3% quicker than the next-fastest popular shoe.

- The “4%” in the name comes from Nike’s finding that the shoe could make its wearers that much more efficient, meaning they need that much less effort to produce the same pace.

- Sports scientist Ross Tucker estimated that the physical output Kipchoge needed for his 2:01.39 world record in the Nike Vaporfly shoes equated to a 2.03 marathon in regular racing flats.

- Nike, who sell the Vaporfly shoes for around $250 in the United States, describe the Next% version as having a “built-in secret weapon” - a full-length, carbon fiber plate underfoot that provides a propulsive sensation to help push the pace.

- An estimated 95 of the first 100 finishers in last year’s Valencia Marathon were wearing Vaporfly shoes, which have an estimated running life of around 200 miles.

- Analysis of the world rankings shows that in 2019, twice as many men ran under 2:10 and twice as many women went under 2:27 as compared to 2016. Eight of the 12 fastest men’s marathons in history have been run in the last year.

- At Hakone Ekiden, a prestigious Japanese relay marathon, the number of runners wearing Asics dropped to seven from 51 the previous year, with 84% of competitors wearing Vaporfly - prompting a fall in Asics share price.

- Nike says its market share in running reached a record high last year on the back of Vaporfly sales.