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On July 7, 1999, Hicham El Guerrouj crossed the line at Rome’s Stadio Olimpico to set a mile time of 3:43.13. Nobody has run a mile faster in the 27 years since. Only one other person, Noah Ngeny, who finished second in that same race, has ever come within a second of the mark. On Saturday, Scottish middle-distance star Josh Kerr plans to take the record down in front of roughly 60,000 fans at the London Diamond League meet.
He announced the attempt back in March and gave it a name: Project 222, a reference to the 222 seconds it takes to run a 3:42 mile. Kerr has been open about why he thinks a 27-year-old record is finally within reach. Tracks are faster and aerodynamics are better understood than they were in 1999, and racing footwear has changed almost completely. Brooks, which has sponsored Kerr since 2018, spent the past five months building him a one-off spike called the Hyperion 222, plus a custom speed suit, both engineered to work at exactly one pace. I talked with Danny Orr, senior director of product development at Brooks, about how you build a shoe for a single race.
Three careful laps and a kick won’t cut it
Kerr won his 2023 world title in the 1500 meters the way championship races usually get won. “You kind of run around for three laps, you keep everybody in your line of sight, you know what’s going on, and then the last lap is really fast, and people tend to win that way,” says Orr. “But you’re never going to break a world record that way.”
A record attempt starts flat out and stays that way until the finish line. It entails four laps at roughly 55 seconds apiece with no tactical coasting and no closing surge. That single difference dictated nearly every design decision in the spike. “The notion of running slowly, or the notion of changing gears or speeding up, they’re going to feel awful in this shoe. It’s just not designed to do that,” Orr says. “It really is a weapon for him to run four laps at a really high speed and a really high cadence.”
Orr’s team started with data Brooks has collected on Kerr over eight years, including high-speed video, pressure data, and VO2 testing done on the track. From there, the designers layered on the specifics of this one event: the expected temperature in London, the target cadence, and the pace he has to hold from the first step.
A sole shaped like a bicycle tire
The geometry is the part a casual observer would notice first. “The midsole and outsole plate of this shoe is a little bit shaped like the bottom of your bicycle tire, in that it has this real curvature to it,” Orr says. That aggressive rocker only makes sense at world record pace. A jogger lands heel first, then rolls through the midfoot to the forefoot, and that curved profile would fight them the whole way. “You would almost feel like you were running uphill in the spike,” Orr says. “Whereas someone like Josh running at that speed, he’s not landing on his heel. He’s landing on his midfoot, then onto his forefoot, and it’s almost like he’s running slightly downhill.”
Stiffness was the other big variable. Kerr is large for a miler, with a bigger foot than most of his competitors and the leg strength to match. “His ability to generate force is higher than a lot of other people that we would work with in this space,” Orr says. “The spike is much stiffer than anything that we’ve ever made before.” The carbon fiber plate is tuned to how much force Kerr specifically can drive into the track, a number that would leave a lighter runner fighting the shoe instead of riding it. Brooks says it used finite element analysis, the same computational modeling that aerospace and automotive engineers use to simulate stress on parts, to settle on the plate configuration.
When I asked what a recreational runner would feel if they laced on a pair, Orr didn’t sugarcoat it. He suggested they’d be better off starting with a road racing shoe, because the Hyperion 222 would feel punishing at any speed slower than Kerr’s.
New materials inside old rules
Brooks kept the upper familiar so Kerr wouldn’t have to adapt to a completely alien shoe, shaping it to a last built from his foot. The radical stuff lives on the bottom of the shoe. “The materials that are providing the energy return, the materials that are providing the stiffness, and even the materials that are providing the traction between his foot and the track surface are all very unique to us,” Orr says. “We’ve never utilized any of these materials in a track spike to date.” The traction includes permanent titanium pins, which Brooks says aren’t available on any mass-market spike, and the outsole carries 222 carbon fiber traction elements as a nod to the target time.
While the goal is to push the tech as far as possible, there are rules in place that keep things in check. World Athletics regulates competition spikes tightly, and a one-off world record shoe gets no exemption. “There are height measurements at 12 percent and 75 percent along the midsole that have to be below a 20-millimeter height, and then there are restrictions in terms of the number of plates that are able to go into the midsoles of these shoes,” Orr says. Every brand designs to the same limits, so the advantage has to come from optimizing within them.
The validation process ran right up against the deadline. Kerr took competing prototypes to an independent lab in Colorado to measure which version produced real benefits, and the Brooks team then replicated those results in Albuquerque before locking the final build. The finished spike arrived last week, cleared World Athletics approval, and was hand-carried to Kerr in the UK days before the race.
A speed suit built for heat and silence
The apparel team followed the same playbook. Brooks ran 3D body scans of Kerr and built the suit one-for-one to his shape, with a sleeveless high-neck silhouette, minimal seams, and a plain front zipper because that’s what Kerr prefers. Aerodynamics led every material decision, but heat management came in a close second. The forecast for Saturday afternoon in London calls for temperatures in the mid-70s Fahrenheit, warm for a record attempt. “Anything that happens that really increases his core temperature significantly for an extended period of time is going to make it that much more challenging for him to break this record,” Orr says. Laser-cut perforations in the suit’s lower half vent heat without compromising the compressive fit, and the fabrics had to stretch through a stride that gets very long at better than 16 miles per hour.
Brooks’ videos about the project mention that the suit is completely silent, and when I asked Orr whether that was an actual engineering target, he pointed to Kerr’s mental approach rather than the fabric. “Josh talks a lot about being in a flow state, and some of his performances come in an environment where he’s in this flow state, where he’s not hearing the crowd,” Orr says. “He’s not really all that conscious of what’s happening in and around him, and he’s really focused on the job at hand. A big part of the conversations with him on the apparel side is what are some of these elements that can just remove the noise.” Sixty thousand people will be screaming at him, but for athletes at this level, a subtle, persistent rustle from a garment can seem insurmountable.
What happens to the spike after Saturday
Kerr trains in the Hyperion 222, but only for his hardest, fastest efforts. Anything sub-threshold happens in something else, because the geometry works against slower paces. The shoe itself is a starting point rather than an endpoint. “This shoe is step one on our plan for LA ’28,” Orr says, referring to the 2028 Olympics in Los Angeles. “This is iteration one, and we’re going to make changes to this in iteration two and three.” A championship version would look different, since tactical racing brings back the gear changes this spike deliberately ignores.
Brooks made extra pairs and plans a public release. “It’s going to be very, very limited,” Orr says, and screenshots have already leaked across running forums since the shoe appeared on the World Athletics approved list. The record attempt itself happens inside a real race. Olympic medalist Yared Nuguse and NCAA record-setter Ethan Strand have both entered the field, so Kerr has to beat the clock and everyone else at the same time. Orr will be watching from the stands, and he told me he expects to be nervous the whole 222 seconds.
