'Super spike' shoes expected to help break records, but experts split on how they work
Sprinter Usain Bolt has called the new technology 'weird and unfair'
A record held for more than a decade by Usain Bolt could be beat at the Tokyo Olympics thanks, at least in part, to shoes.
Athletes wearing so-called super spikes, a new family of shoes worn by sprinters, have slashed records in recent months. In June, Jamaican Olympic gold medallist Shelly-Ann Fraser-Pryce ran the fastest 100-metre in 33 years wearing a pair of Nike Air Zoom Maxfly shoes.
But footwear biomechanist Laura Healey, who has studied gains in athletes who compete with the shoes, says there's more to the recent broken records than just the footwear.
"The shoe, we are seeing, does contribute to these improved performances, but there are lots of other things. The athletes are obviously incredibly talented and they've been training really hard," said Healey, who is also manager of footwear innovation for Puma.
"If we compare it, for instance, to their times last year, we can't [attribute] their gains all to the shoe because there's lots of other factors to why they might get faster."
Super spikes, which are now available from a variety of the biggest sports brands — including Puma — are facing criticism for their perceived increases to a sprinters' speed. Bolt, who retired from competition in 2017, made his feelings about the technology known this month, calling the shoes "weird and unfair."
Currently the fastest sprinter in the world, American athlete Trayvon Bromell is a favourite to break Bolt's 100-metre record — and, unsurprisingly, he's expected to compete in a pair of super spikes.
The shoe's purported boost comes from its construction. Rigid plates beneath the forefoot and thick, plush soles reduce energy loss while running, but there is little quantifiable data on how the shoes impact performance.
"It's hard to say which exact features are contributing the most," Healey told Day 6 host Brent Bambury, noting that athletes will respond differently depending on the shoe.
'Acts like a spring'
Benno Nigg, a professor emeritus of kinesiology at the University of Calgary, studies the technology of sports shoes and has worked with manufacturers throughout his career. He likens recent developments in shoe technology to that of changing track surfaces in the 1960s.
The transition from running surfaces made of natural materials, like cinder, to artificial ones in competition benefitted sprinters' speed, he explains.
"If you look at the world records at that time, you have to make an asterisk by the name because it's a different situation, and I think they have to do the same thing if they allow these shoes," Nigg said.
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He believes that super spikes have played a "substantial" role in recent record-breaking runs, attributing the gains to better energy return offered by the thick soles.
"They are thicker under the ball of the foot, and that thicker part acts like a spring," he said.
World Athletics, the international body that regulates track and field events, sets rules around what shoes can be used in competition.
A July 2020 amendment, intended to provide certainty for athletes seeking to compete in the 2020 Tokyo Olympics, set a maximum sole thickness of 40mm, or 20mm for track events up to 800 metres.
In a statement, a spokesperson for World Athletics told Day 6 that most manufacturers have introduced new shoes to the market ahead of the Olympics.
"All new shoes and prototypes have been and will continue to be reviewed against the current regulations before being allowed to be worn in international competition," the statement continued.
Records will be broken, says Nigg
Healey says that the recent regulations are evening the field for athletes, but acknowledges that shoes at this year's Olympics are a far cry from shoes of the past.
Still, she hopes to see the technology embraced.
"I don't think that they should be banned. I think that the limits [on new shoes] are important to set," she told Bambury. "I love to see the innovation and what we can do to make humans run faster."
Now, with all eyes on the track and field events at the Olympics, fans and experts alike are awaiting the results.
And Nigg, a sprinter himself, expects to see some record-breaking runs.
"It'll be fun," he said.
Written by Jason Vermes. Interview with Laura Healey produced by Sameer Chhabra.
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