Why Is Everyone Running So Fast in 2025? Super Spikes 3.0, A Golden Generation of Americans, and…Bicarb?

Thank you for being an SC member. This is an SC exclusive.

At this time in 2023, toward the end of an indoor season during which athletes like Yared Nuguse and Katelyn Tuohy were breaking records left and right, I wrote an article trying to explain what was going on in American distance running. My opening paragraph finished with the following sentence:

Through the first two months of the year, we’ve seen five collegiate records (women’s mile, 3,000 & DMR, men’s 3,000 & DMR), four American records (men’s mile, 3,000, & 5,000, women’s 3,000), and even a world record (men’s 3,000).

That seems quaint compared to what we have experienced so far in 2025. Nine of those 10 records set in 2023 have already been broken — eight of them in the last three months. And that barely scratches the surface.

In a one-week span from February 8-14, 2025, we saw five world indoor records (men’s 3000m, men’s mile, men’s 1500m, men’s mile again, men’s 5000m) and men’s American records in every major indoor distance (800m, 1500m, mile, 3000m, 5000m). Three of those world records were set by Americans Nuguse and Grant Fisher, two of them on the same afternoon at the Millrose Games in New York. It is hard to tell which is stranger: that, more than 20 years after the most recent world record by an American distance runner (Khalid Khannouchi, 2:05:38 marathon, 2002), two were broken within the span of two hours. Or that the two Americans directly behind them, Cole Hocker and Hobbs Kessler, also ran under the previous world records.

Kevin Morris photo

In all, the 2024-25 indoor season has produced eight NCAA records, six American records, and five world records in events between 800 and 5,000 meters. And in many cases, multiple athletes have run under the previous record. Six of the seven fastest men’s indoor milers in history have set their PBs in 2025. Four men ran under the NCAA 3,000m record in the same race in December; not to be outdone, five women’s teams ran under the previous NCAA distance medley relay record in Seattle last weekend.

We still have another month remaining in the season, too, with USA Indoors, NCAA Indoors, and World Indoors all yet to come. It is difficult to keep track of all of it (though we have a helpful table below).

NCAA indoor records in 2024-25 indoor season

American indoor records in 2024-25 indoor season

*also world record
** en route to mile

World indoor records in 2024-25 indoor season

And this does not even cover the roads, where we saw American records in the half marathon by Conner Mantz and Weini Kelati in Houston last month and a 56:42 world record from Jacob Kiplimo on Sunday.

So I ask, for the second time in three years: what the hell is going on? After talking to some of the athletes and coaches behind the record-setting 2025 indoor season, a few factors stand out. Runners are still reaping the benefits of recent developments in shoe technology, which has had knock-on effects on training philosophies. In many events, the top Americans are now among the very best in the world, and they’re willing to chase fast indoor times to a far greater degree than their foreign contemporaries. And many of those athletes are using sodium bicarbonate — which may help, even if remains unclear to what degree.

1) Supershoes/Superspikes 3.0

Any discussion of records in the year 2025 has start with the improvements in shoe technology that have revolutionized distance running over the past decade. Advanced foams and carbon plates in shoes and spikes have allowed athletes to recover faster and run more efficiently at high speeds. At this point, their impact is undeniable.

But supershoes have been widely available since ~2018 and superspikes since ~2021. So why are we still seeing big breakthroughs in performance?

One way to think of it is that we are now witnessing third-order effects of shoe-related performance gains. The first-order effect was simple: wear the shoes in a race and you will automatically run a little faster than before. Second-order effects came in training: better foam meant athletes could run faster in practice and recover more quickly. North Carolina coach Chris Miltenberg told LetsRun.com his athletes now do significantly higher volume in workouts than the likes of Fisher and Sean McGorty did when they won NCAA titles for Miltenberg at Stanford in 2017 and 2018. Miltenberg’s current stars, UNC seniors Ethan Strand and Parker Wolfe, are reaping the benefit of four years of training in super spikes.

Kevin Morris photo

“We always talk about it like an investment,” Miltenberg said. “It’s compound interest: we’re able to train 10% harder, 10% sooner [after races], 10% more often.”

Now, the super shoes are starting to change how coaches structure their athletes’ training and racing schedules. More top coaches — at both the college and professional levels — are incorporating new training systems like double threshold that allow their athletes to run a higher proportion of their weekly mileage at threshold pace.

“ This fall, we did more double threshold than I had done probably my entire three years here previously,” said Strand, who has set NCAA records in the mile (3:48.32) and 3000m (7:30.15) this season.

“The training has evolved in big part because of the shoes,” said Pat Henner, who coached Miltenberg and NAU coach Mike Smith at Georgetown in the 1990s and 2000s and now coaches Hobbs Kessler alongside Kessler’s father, Mike. “Now you can do the double thresholds, people are running 24 x 400 and running them pretty fast. So therefore you’re doing aerobic work and it’s still base work, but now you’re getting paces that are much closer to the actual race pace.”

Both Miltenberg and Henner have noticed athletes being able to race faster, earlier compared to previous years.

“Hobbs before this indoor season, if you want to say hard, specific workouts? He did three or four, maybe,” Henner said. “So I think you can just get a lot closer to ‘racing fitness’ with just your short sprints and your lactate threshold training than you used to be able to.”

Stephen Haas, coach of Under Armour’s Dark Sky Distance team in Flagstaff, said he believes athletes and coaches have also been willing to incorporate more intensity year-round because the super shoes offer better recovery. There is less fear of going too hard in the winter and burning out by the end of the summer.

“I think there’s a component of adjusting our ideology of when is appropriate to run fast,” Haas said.

2) A Golden Generation That Wants to Run Fast

Advances in footwear has pushed times forward, but they do not explain why Americans are suddenly breaking distance world records. Or why all six of the American indoor records set in 2025 have been achieved by men — if it was just the shoes, we would expect to see a few women’s records too.

Shoes help, but athletes still matter. And right now, the US in a golden era of men’s middle-distance running, with medals in every track event at the Paris Olympics except the men’s 800, where Bryce Hoppel was 4th in an American record of 1:41.67, led by a 1-3-5 finish in the men’s 1500.

The men’s 1500m team in the US has never been harder to make than right now (Kevin Morris photo)

That Olympic success has forced the next generation of athletes to aim higher. Anyone capable of beating out Kessler, Nuguse, or Hocker — all of whom are 25 or younger — for a spot on the US 1500 team this year must, almost by definition, be a World Championships medal contender.

“I know specifically for my two guys, seeing what Grant and Cole did this summer in the Olympics and Hobbs and Yared, the Americans across the board – I think it expanded our mindset of what we think we can do,” Miltenberg said. “…There’s just this continual raising of the bar.”

Meanwhile guys like Nuguse and Fisher, who are already among the very best in the world, know they must keep pushing to improve if they are to keep up with Jakob Ingebrigtsen, who has raised the bar on the global stage just as Fisher, Nuguse, and Hocker have raised it domestically.

“ Jakob has changed the game in a lot of ways and a lot of us are chasing him,” Fisher said. “He’s kind of the gold standard in time now.”

But as good as this generation is, it’s not as if Americans had zero distance success in prior Olympics. Galen Rupp and Leo Manzano both earned silver medals at the 2012 Olympics. Americans claimed seven mid-d/distance medals at the 2016 Olympics — two more than in Paris. Matthew Centrowitz, Jenny Simpson, and Paul Chelimo all medalled three or more times at global outdoor championships. Athing Mu won Olympic and world titles in the 800 in 2021 and 2022.

A number of those athletes either were not capable of ripping crazy-fast times (Centrowitz, Simpson, and Chelimo were always better in tactical races) or had no interest in trying during the indoor season. Sometimes, Rupp or Bernard Lagat would get into great shape and try for a fast time, but they never seriously threatened world records — in part because they did not have superior footwear to the athletes whose marks they were chasing.

Compare that to 2025.

In recent years, the indoor season has become a major focus for top American pros — last year, the US earned seven mid-d/distance medals at World Indoors (Nuguse, Kessler, Hocker, Hoppel, Elle St. Pierre, Nikki Hiltz, and Emily Mackay). All seven of those athletes made the Olympic team four months later, and most of them ran very well in Paris. Fisher didn’t run World Indoors in 2024 but ran two fast races at Millrose and BU, just like this year. It has become the norm for Americans to get in great shape over the winter and let it rip a couple of times in February. Particularly this year, when there is plenty of time to rest after the indoor season and build back up for a late USAs (July 31-August 3) and Worlds (September 13-21).

“I think the timing of the season this year allowed athletes to ramp up their prep a little bit more intensely for the indoor season,” Henner said.

Fisher believes one of the main reasons for the fast times in 2025 is that the best Americans have continued to build on the gains they achieved last winter and summer.

“All the Americans that just ran really well had great Olympics,” Fisher said. “So I don’t think it’s like what’s happening right now. It’s probably what was happening this time last year that led people to run really well at the Olympics and now is leading them to have great momentum in the indoor season.”

Henner said that, both muscularly and aerobically, Kessler is stronger right now than he was at the Olympics last year. Fisher believes he is as fit — or fitter — aerobically than he was in Paris (he’s clearly fitter than he was this time in 2024, when he ran 12:51 in his attempt at a fast 5,000 at BU compared to 12:44 in 2025). Hocker had his best winter of training ever. Nuguse wouldn’t go that far, but he logged another solid winter. All of these guys are still in their primes. With no injuries and another year of training, they logically should be faster than this time in 2024.

“The number one thing that is timeless – that has never changed and will never change – is consistency trumps all,” Miltenberg said. “…Consistency is how you get good. No one super hard workout, no one super hard week, month, year make you. It’s how many days and weeks and months and years can you layer on top of each other?”

Once they are on the track, Nuguse and Fisher also race like men who want to get after it. They head to some of the world’s quickest indoor tracks, like Boston University or the newly-resurfaced Armory in New York, and are not afraid to stick on the rabbits, then keep pushing the pace when they drop out. Which means they are giving themselves — and their competitors, who are happy to follow in their wake — the best chance to run fast times.

Nuguse’s mile world record stood for five days until Ingebrigtsen broke it (Kevin Morris photo)

Another important note: indoor world records are slower than outdoor world records. That’s not because conditions are way better for running fast outdoors. Most of the benefit gained from gentler angles into the turns on a 400m track can be offset by better weather and a bouncier track indoors (the dewpoint was 69 Fahrenheit when Joshua Cheptegei ran his outdoor 5,000 world record of 12:35; Jakob Ingebrigtsen ran his 7:17 3,000 world record when it was 85 and sunny).

The main factor as to why outdoor records are faster is timing. The 5,000-meter world record entering 2025 stood at 12:49.60 by Kenenisa Bekele (outdoor pb: 12:37.35) — a time eclipsed by seven men during the 2024 outdoor season alone (none of whom were named Grant Fisher). Guys like Yomif Kejelcha, Jacob Kiplimo, and Berihu Aregawi didn’t run those times because the outdoor tracks in Oslo and Brussels are faster than the indoor track in Boston. They did it because they were ready and motivated to run fast for 5,000 meters in May and September, not January and February.

Consider: two days after Fisher’s 12:44 world record in Boston, Kejelcha ran 26:31 in a 10k road race in Castellon, Spain. On the same day, three hours north, Kiplimo ran his 56:42 half marathon world record in Barcelona (splitting 26:33 from 5k to 15k). Put those guys on the indoor track in Boston instead, and they would have run faster than Bekele’s 12:49, too.

The fact is, many of the best runners from the super shoe era have not made much of an effort to run fast indoors. Joshua Cheptegei has never run an indoor race. Nor has Timothy Cheruiyot. Aregawi, who ran 7:21 last year outdoors, has not raced indoors since 2022.

Now we are seeing what happens when some of the best runners in the world target indoor times. Five days after Nuguse — whose outdoor pb is 3:43.97 — ran his 3:46.63 at Millrose, Ingebrigtsen (outdoor pb: 3:43.73) ran 3:45.14. That race was Ingebrigtsen’s first-ever mile indoors. Since the start of 2020, Ingebrigtsen has run only four indoor races outside of European/World Championships. Despite that, he has set three indoor world records in that span.

What Fisher and Nuguse did to break their world records was still very impressive, of course. Reminder: during his 3,000, Fisher ran world record pace from the front for 12 laps, then outkicked the reigning Olympic 1500 champion to run 7:22.91 (and the record he broke, Lamecha Girma‘s 7:23.81, was a supershoe record). That is incredible.

The bottom line: in 2025, we have a group of Americans who are among the very best in the world racing on super fast indoor tracks deciding to get in great shape and take aim at records that, in some cases, have not been seriously attacked during the super shoe era. Now we are seeing the results.

“Is it a golden generation of talent?” said Fisher’s coach Mike Scannell. “I don’t think so. I think there is a group of very motivated [guys] and aggressive training…And the opportunities have changed and I think these guys are taking advantage of it.”

3) Bicarb?

Sodium bicarbonate — “bicarb,” for short — has long been touted as a performance-enhancer because of its ability to buffer hydrogen ions in the muscle during intense exercise, allowing athletes to push for longer before they begin to “feel the burn.” For many years, athletes resisted using it in its most basic form — baking soda — because it could lead to cramping and gastrointestinal distress.

But over the past two years, the use of bicarb has exploded in elite middle-distance running, thanks largely to Maurten, a Swedish company that created an innovative delivery system for bicarb that minimizes the negative side effects. More than half of the distance medalists on the track at the 2023 World Championships used bicarb (we did a deep dive on bicarb afterwards: LRC The Pill That Over Half the Distance Medallists Used at the 2023 Worlds).

So how much of a role is bicarb playing in the spree of fast times?

It is hard to say. Evidence is growing that the Maurten Bicarb System really does boost endurance performance, but we are not yet at the point where we can say that definitively. Many of the world’s best athletes use it. Olympic 800m champions Emmanuel Wanyonyi and Keely Hodgkinson use it. Jakob Ingebrigtsen has been said to have used it for years. Canada’s Marco Arop had never run faster than 1:42.85 before trying bicarb at last year’s Olympics, then ran 1:41.20 in Paris, followed by 1:41.72 and 1:41.86 in his next two races.

Of course, athletes also run personal bests at the Olympics because that is when they are in the best possible shape. Like Hoppel, who did not take bicarb in Paris and dropped his pb from 1:42.77 to 1:41.67 in the Olympic final.

It is a similar story in the US. Josh Hoey began using it in 2024, the year in which he improved his 800m pb from 1:47.36 to 1:43.80. Kessler has used it for a couple of years, but it’s important to note that Nuguse, who beat Kessler to the WR at Millrose, does not use it. Ethan Strand (who has an NIL deal with Maurten), uses it and believes it makes an impact. The University of Virginia’s Gary Martin also used it before running his 3:48.82 mile at Millrose, which moved him to #2 on the all-time NCAA list behind Strand. But Strand’s UNC teammate Parker Wolfe — who ran 7:30.23 for 3,000 in December, just .08 behind Strand — is not a bicarb fan.

Fisher used bicarb before both of his world records this year. But he admits he does not know how much it helps — or whether that aid is physiological or mental.

“I think definitely in the 1500 and 3k it helps,” Fisher said after his 5,000 world record. “5k on up, I haven’t used it enough to really know. But I think it makes an impact. If that impact is 1%, that would be massive. It’s probably more like 0.1%, if there is one. And if it is just mental, then I’ll take that, too.”