© Kirby Lee-USA TODAY Sports

Ethiopian distance runner Derara Hurisa became the latest athlete to join the trend of setting new records in the sport. At Sunday's Tata Mumbai Marathon, Hurisa set a course record when he finished the race in two hours, eight minutes and nine seconds. It was impressive feat made only significantly more so when it was revealed that not only had the Ethiopian never run a marathon before -- he had only competed in cross country events -- but he also had to run the race in borrowed shoes as his got lost on the flight over to the competition.

Oddly enough, the shoes, not Hurisa, are the main character in this story. The marathon winner borrowed a pair of Nike Vaporfly running shoes from a fellow elite runner. In doing so, he unintentionally added fuel to the fire of a controversy that has surrounded this pair of kicks in recent months. 

The Vaporfly has been a leading subject of discussion for World Athletics, the governing body for most of the world's running events, about whether these shoes give runners an unfair advantage. Since it first launched in 2017, the Nike product has been proven to give runners a 4 to 5 percent improvement on their running economy, the energy utilization measured when a person runs at a competitive (or generally aerobic) speed. 

A recent unreleased model, called the AlphaFly, has particularly captured World Athletics' attention in part due to layered graphite plates that the shoe has inside of it. The supposed concern here is that in allowing that material in the shoe, it would return an unfair amount of energy to the runner that was expended compared to others. This would especially cause problems with athletes that weren't sponsored by Nike, as they'd have a known inherent disadvantage against their competitors. Red flags were raised after professional runner Eliud Kipchoge wore the unreleased Vaporfly model during his successful attempt to run the first-ever sub-two hour marathon.

If it was just a matter of that one model being an issue, perhaps the decision on whether to ban that shoe from competitions wouldn't be taking so long--plus, athletes could at least use earlier models of the shoe that omitted the graphite plate. But World Athletics will be revealing their findings at the end of January, according to Reuters, as the concern extends to the Vaporfly line as a whole given that so many records have been shattered by Nike athletes in the time since the shoes' release.

Here are a few of those records, courtesy of Reuters:

  • Kipchoge 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.
  • 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).
  • 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%.
  • 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.
  • 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.

Of course, none of this is meant to minimize what Hurisa accomplished in Dubai earlier this week. A near-two hour marathon is an incredible pace, especially for someone wearing unfamiliar shoes and having never competed in such a race before. The problem is that because this achievement was done at this particular moment in time, it may become a case study for why these shoes shouldn't be on the feet of distance runners in the first place.