Olympian and Key Vaporfly Researcher Shalaya Kipp Talks to LRC About World Athletics’ New Shoe Regulations

“Actually the whole time [we were studying the Vaporfly prototpe], we were calling it ‘The Magic’ because we didn’t have a name for it and really whenever we put someone in the shoe in the lab it seemed like a magical result that was coming out”

By Robert Johnson
January 31, 2020

After World Athletics released its new shoe rules today, we recorded a special bonus podcast about the ruling. We invited 2012 NCAA steeplechase champ and US Olympian Shalaya Kipp, who is now a PhD candidate in Exercise Physiology at the University of British Columbia, to be our expert guest. Kipp, along with others, including Wouter Hoogkamer and Rodger Kram, has published three different scientific papers dealing with the technology behind the Nike Vaporfly shoes. We could think of no better guest to feature than Kipp; she was part of the study published in November 2017 that actually gave the Vaporflys their 4% name as the scientists behind that study found that they boosted running economy by 2-6%.

You will eventually be able to listen to the whole podcast here, and we encourage you to do so as it was fascinating to hear from Kipp. But if you don’t have 23 minutes to listen to Kipp, then we’ve got virtually all of her best comments transcribed for you below. She reacts to the ruling, talks about what it was like to watch the marathon in 2016 knowing the Nike athletes had a huge advantage, and how she believes the new shoes kept her training partner Kara Goucher off the 2016 Olympic team.

Shalaya Kipp, after making the 2012 US Olympic team. More 2012 US Olympic Trials Photos.

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Shalaya Kipp overall is very pleased with World Athletics’ new shoe regulations

I guess the thing I was most excited to see was that no prototypes can be used in subsequent competitions [after April 30, 2020,] and that the product needs to be on the market for at least four months. That really made me happy… Putting that four months in there, I liked that a lot…

We point the finger at Nike but really everyone is running in prototypes – we’ve got to remember that…

The fun scientist in me doesn’t want to limit innovation too much. I think it’s great that someone wanted to go out with a waffle iron and start creating their own shoes. I don’t want to put too many limits [on innovation]. What I do want to see is that the athletes aren’t getting the butt end of that. [I want it to be fair] for all of them. I’m happy with the limitations that came out. I wouldn’t have added anything.

Shalaya Kipp thinks other shoe companies will catch up with Nike and that the playing field will be level “within a year or two.” In the interim, she urges the non-Nike companies to let their athletes race in Nikes. “They need to let their athletes run in the Nike Vaporfly right now if they want their athletes to be performing well or they are going to be at a disadvantage.”

You know I think it’s definitely feasible [for the other companies to catch up]. I don’t think it’s that hard for them… As long as they start developing their own foams, getting a carbon-fiber plate in there. We’re going to see it happen. It’s going to take a little catchup but within a year or two, I think it’s going to all become a wash again and the playing field is gonna become level… Maybe I’m an optimist. I want that for the sport.

I really hope that those shoe companies are doing their own internal tests and they know how well their shoe is performing. And if their shoe is not up to standards, they need to let their athletes run in the Nike Vaporfly right now if they want their athletes to be performing well or they are going to be at a disadvantage. We know that that shoe is working well and that it’s creating all the results.

Shalaya Kipp talks about what it was like to know that Nike had shoes that were way better than anyone else in 2016. The shoes were so good the researchers nicknamed them “The Magic” as they were producing “magical” results in the lab.

[In our study, we tested] the shoes that they used in Rio and it was the same shoe they used for the Olympic Trials…It wasn’t [called] the Nike 4% at the time as that comes from our findings. All [Nike] said was “this shoe is special.” And actually the whole time we were calling it “The Magic” because we didn’t have a name for it and really whenever we put someone in the shoe in the lab, it seemed like a magical result that was coming out. 

Kipp talks about how she believes Kara Goucher would have been an Olympian in 2016 had she had the Vaporfly prototypes

I remember knowing when we watched the [US] Olympic [Marathon] Trials that the shoe was [worth] about a 4% savings…I was training with Kara Goucher at the time and she had just signed with Skechers and I kind of remember thinking that if that hadn’t happened and she had stayed with Nike, she’d be making a third Olympic team but she’s running for wrong company right now.

Even though Kipp says “mechanical doping” in 2016 took place, she doesn’t think it’s beneficial to look back. She is interested in how the new rules will be implemented moving forward

I mean you can’t go back and change a team [or results] as that’s past [us] but I am interested in seeing how this will be implemented. What do you do in future Olympic Trials? Do you have those athletes cross the finish line and [then have the] doping control agent come and say, ‘You are going to stay with me until I get your sample and [until] I take your shoes. I’m taking your shoes right now and I’m getting the calipers out and I’m going to run them through an x-ray to see how many plates are in it.’

I can’t really look back but I am interested to see, will we do some concrete things in the future to control for mechanical doping?

Shalaya Kipp talks about how we’ll never know how fast Eliud Kipchoge would be without the new shoe technology

I don’t think we’ll ever know that for sure…When we look at those extrapolating models, we’re not accounting for how that efficiency is going to change over the duration of the [full] marathon. That 3% efficiency savings that we’re [talking about], it could be diminishing over the [full] marathon so you’d actually get less performance from the shoe. We don’t know that. Our lab-based studies are based off five-minute trials as you can’t have someone come in and run six marathons in a row. 

Kipp is still dreaming of Olympic team #2 (she was 4th at the 2016 Trials after making it in 2012)

I hoping to be healthy on the start line come June 19 (the first day of the Trials).

Listen now as a podcast:

Links to Kipp’s scientific research related to the Vaporflys:

A Comparison of the Energetic Cost of Running in Marathon Racing Shoes

Extrapolating Metabolic Savings in Running: Implications for Performance Predictions