As the past fortnight has demonstrated, marathons are becoming as much about brands as they are the runners.
Two of the biggest hitters in sportswear, Adidas and Nike, are battling to be involved with the first athlete to break the magic two-hour mark in a marathon.
Dr Thomas Allen, senior lecturer in sports engineering at Manchester Metropolitan University Institute of Sport, told BBC Sport: “It’s important to not take it away from the athletes.
“They are improving with training techniques, nutrition and support from sponsors. All of this contributes.
“The shoes are helping but it’s just a small improvement. Athletes have to be very good but there is evidence to say the shoes are helping. Many athletes are wearing these advanced shoes.”
Adidas boasted about their athlete Assefa making history in Germany, and Nike were quick to post on social media after Kiptum’s success on Sunday.
The women’s Chicago Marathon was won by Hassan, who set a course record wearing Alphafly 3s.
Former Great Britain long-distance runner Richard Nerurkar told BBC Sport: “The shoe technology that has come in in the last five years has made a huge difference in terms of how fast people are running. So we can’t deny that.
“But marathon running is a very, very tough sport, so to run fast or to run very fast or to break world records you’ve got to train incredibly hard.
“Kiptum who broke the world record in Chicago and Assefa who broke the world record two weeks ago in Berlin, they have to be applauded for their hard work in training. Some people would say it’s the shoes and the shoes alone, but I would say it’s a combination of a lot of hard work and obviously shoe technology.”
