Nigeria’s Tobi Amusan reignited the debate about track and field’s new super shoes as she unexpectedly shattered the 100m hurdles world record in Eugene.
On a night when Mondo Duplantis also broke his own pole vault world record, Amusan ran a staggering 12.12 seconds in her semi-final to beat Kendra Harrison’s old best by 0.08 sec – smashing her personal best time by nearly three-tenths of a second.
Immediately after the race, the former world 200m and 400m record holder, Michael Johnson, wondered whether the timing system at Hayward Field was off. He was far from alone. However it transpired that Amusan had been given a boost by using Adidas Adizero Avanti shoes, which are designed for 5km and 10km runners, rather than track spikes.
After running even faster to win gold in the final nearly two hours later, Amusan revealed she had accidentally stumbled on the idea of using the shoes, which have extra bouncy foam, after injuring her foot.
Adidas bill the Adizero Avanti as “like hitting fast-forward” and promise the shoes “provide a snappy, propulsive ride with high traction and reduce fatigue, so you finish 5km and 10km races with a kick”. There is nothing illegal about the shoes, with current World Athletics rules dictating that sprint spikes cannot have soles thicker than 20mm – the same as the Adizero Avanti.
Until now these shoes have always been used for long races, but the benefits for Amusan were obvious as she flew high over the hurdles and into the record books. “My abilities are not centred around spikes,” said the Nigerian, who ran 12.06 in the final, only for the wind speed of +2.5m/s to make it ineligible for record purposes.
“I had patella fasciitis at the beginning of the season so that set me back for a while,” Amusan added. “I spoke to Adidas and requested if I could get spikes with a softer sole. They recommended a lot of stuff and I feel comfortable in [the shoes], so I was using them basically the entire time.”
The new breed of super shoes do appear to particularly help hurdling events, with Sydney McLaughlin also breaking the women’s 400m hurdles record wearing New Balance’s latest model earlier this week.
There was another world record at the finale of these championships as Duplantis cleared 6.21m. The Swedish vaulter won another gold medal – and, like Amusan, left Eugene with a bonus cheque of $100,000.