Chepngetich has a storied history in the marathon, winning the world title in Qatar in 2019 and coming within 14 seconds of a previous world record attempt.
However, its strong improvement over time was more noticeable in ‘super shoe’ era.
Between 1988 and 1998, the men’s marathon world record was unchanged.
Now the breakthroughs are more regular and more pronounced.
In just over 10 years, the men’s mark has quadrupled, with nearly three minutes wiped off the clock.
Chepngeticheva’s third new world record for women in five years, with the fastest woman’s time over 26.2 miles reduced by five and a half minutes in that period.
High-tech foams, carbon panels and pressurized airbags are combined in the soles of the latest shoes to return more energy to athletes, sparking an arms race between manufacturers.
World athletics has moved quickly to regulate shoe technology.
Chepngetich was wearing the Nike Alphafly 3, one of hundreds of different models that have been verified, confirmed and published on World Athletics website and dedicated app., external
Regulations on shoe technology are stretching 18 pages, external and include limitations in the development of ‘intelligent’ shoes that could alter the composition of the sole in different parts of a runner’s stride pattern.
Manufacturers are permitted to supply sponsored athletes with prototype shoes that are not yet available to the public for testing purposes outside of the Olympic Games and World Championships.
However, other approved shoes must be or have been available to the general public. Chepngetic’s chosen pair retails at £285.
Kenyan long-distance running has been affected by doping scandals in recent years, and Chepngetich was asked about doping after her win in Chicago.
Former marathon world record holder Wilson Kipsang, former half marathon world record holder Abraham Kiptum, Rio 2016 Olympic marathon champion Jemima Sumgong and London Marathon winner Daniel Wanjiru are among those banned.
World Athletics President Lord Coe visited Nairobi in January 2023, but Kenya’s anti-doping agency says it has since been weakened by government budget cuts.
Asked if she understood why the positive tests might cause some fans to question her new world record, Chepngetic said: “People need to speak up.”
