Maurten spent months working with Sawe and other runners getting their gut capacity trained so they could absorb and burn 100 carbs per hour[0][1]
> The Maurten research team was embedded with Sawe’s team in Kenya for 32 days across six trips between last and this April. They were training his gut to absorb that load by mimicking race-day protocol in training. The hydrogel technology they have developed over the past 10 years now allows athletes to absorb 90–120 grams of carbs per hour without GI distress.
Second is the shoes. Adidas Adizero weigh 96 grams[2] with new foam tech and new carbon plates
Nike and INEOS spent millions over years to get Kipchoge to a sub-2 in artificial conditions, and now the elite end of the field are knocking that barrier out in race conditions. Unreal.
Running tech and training have been revolutionized in the past few years.
[0] https://marathonhandbook.com/sebastian-sawe-arrives-in-londo...
[1] https://www.instagram.com/p/DXmvAUvkWaq/
[2] https://www.runnersworld.com/uk/gear/shoes/a71129333/sabasti...
edit: correct :s/calories/carbs thanks
burning a hundred calories an hour is trivial. Most people will burn 100 calories per mile when walking or running, and more if moving as fast as these athletes, and many, many humans can do this for far, far longer than 2 hours.
It's the absorbtion that's the challenge. Maurten is not somehow alone in the particular stuff they've developed - ultra runners are generally shifting up into the 90-120 gram/hr range (or beyond!), using a variety of different companies' products. The gut training protocols for this are widely discussed in the world of running for almost any distance above a half marathon.
GP left out the units but is clearly talking about grams ("absorb ... 100 carbs per hour"), not calories (no one needs training to absorb 25g/hr). Carbs are 4 kcal/g. 100g of carb (400 kcal) an hour isn't replacement level for even casual athletic efforts, but it does mitigate the loss of glycogen in muscle somewhat.
> Even if you can absorb 120 grams per hour, it might not make you faster. In Podlogar’s study, cyclists burned more exogenous carbs when they consumed 120 rather than 90 grams per hour, but that didn’t reduce their rate of endogenous carb-burning—that is, they were still depleting the glycogen stores in their muscles just as quickly.
https://www.outsideonline.com/health/training-performance/en...
Is that all the science to it?
So ~2800 calories of carbs with some fat being burned.
The race to tolerate lots of carbs is usually something you think of in 8 hour Ironmans. The good part is you can do most of it on the bike, which is much easier to eat as you go. As far as I know, many elite runners were doing like 50% water, 50% sports drink and consuming way under 100g.
This used to be true, and is still true for many athletes up the marathon distance. Above that, however, the momentum has swung heavily to very high carb intake. Most (though not all) of the world's best ultra runners (we're talking 7:00 min/mile pace through mountainous terrain) are picking this up, with many getting to and beyond 100g/hr of carb consumption.
It was confusing when the running industry switched from calories to grams of carbs, but that's all anyone talks about now.
"In the aerobic exercise domain up to ~100% of maximal oxygen uptake (VO2max), CHO is the dominant fuel, as CHO-based oxidative metabolism can be activated quickly, provide all of the fuel at high aerobic power outputs (> 85-90% VO2max) and is a more efficient fuel (kcal/L O2 used) when compared to fat."
https://www.gssiweb.org/sports-science-exchange/article/regu...
1 food calorie as listed on a food label is enough to heat 1kg of water by 1c
https://www.futilitycloset.com/2008/11/16/the-mensa-diet/
(If the nutritional calories in the drink had been only the same number of thermodynamic calories, the drink would have been energetically negative for the body because of its low temperature.)
But yeah, this is a thing. There is some gut distress for sure at higher levels of intake. See guy finishing second -- still under 2 hrs! immediately puking, which is fairly common at the high intakes. I've heard of Blumenfeld (the triathlete) taking like 200g/hr or more. Insane. Though he's had some epic GI disasters too, lol.
adidas introduces the Adizero Adios Pro Evo 3 – the lightest and fastest Adizero shoe ever, weighing an average 97* grams.
The race-day shoe represents the culmination of three years of cutting-edge research. It is 30% lighter, delivers 11% greater forefoot energy return, and improves running economy by 1.6% compared to its predecessor - making it a record breaker before it’s even laced up.
The shoe will launch with a highly limited release, with ambitious runners able to sign up for the chance to get their hands on a pair from April 23. This will be followed by a wider release in the fall marathon season. The Adizero adios Pro Evo 3 will cost $500/€500.
The Nike Alphafly 3 is the lightest in the series, weighing approximately 7.0–7.7 oz (198–218g) for a men's size 9, and 6.1 oz (174g) for women's sizes.
The PUMA Deviate NITRO™ Elite 3 is exceptionally lightweight, typically weighing 194g (6.8 oz) for a men's size 8 (UK)> Improved durability: Supercritical foaming produces a more consistent cell structure in a midsole. This should translate to pressure and weight being more evenly distributed, which should lead to greater durability of the midsole. “We’ve done a lot of testing of what foams look like on a dynamic impactor fresh versus 300 or 500 miles later, and we see less degradation in those materials longer-term,” FitzPatrick says.
> At least in terms of the midsole’s life span, super foams may have done away with the conventional benchmark that running shoes last about 300 miles. “I think it’s a dated standard,” Caprara of Brooks says. “It’s an easy go-to to help simplify. But every foam is different, and it’s not just the foam—it’s how it’s constructed, the shoe’s geometry, the rubber underneath it. There are so many factors. If I were to tell you the Glycerin Max lasts 300 miles, that’s probably less accurate than it is accurate. It’s probably closer to 500.”
https://www.runnersworld.com/gear/a64969945/secret-to-super-...
I’m sure someone will happily sell them to you if you enjoy wasting money.
The continental rubber outsole on these Adidas Adios Pro EVO 3 shoes are so thin (less than two sheets of paper, I think), that they don't even appear in side/profile views of the shoes. The outsole doesn't even extend the length of the entire shoe, it stops around the middle of the shoe. So heel strikers aren't welcome and will have loads of fun in wet weather. see https://www.adidas.com/us/adizero-adios-pro-evo-3/KH7678.htm...
In general, these high stack, forward-leaning shoes are meant for going straight ahead - imagine ladies' high heel shoes with an inch and a half of foam on the bottom - any sharp turns will force the runner to slow down or they'll twist their ankles. Looking at the London Marathon course, https://www.londonmarathonevents.co.uk/london-marathon/cours..., there's about twenty ninety-degree or sharper turns.
It's easier to draw attention (and therefore sponsorships) if you leave some room to improve on successive attempts. It's riskier to give everything up front and then risk plateauing or regressing in your subsequent attempts.
Super shoes. Most shoes have carbon plates in them now, they act as a spring, storing energy and propelling athletes forwards.
Better understanding of fuelling. Most athletes are taking between 100-120g carbs (sugar) per hour. Bicarbonate of soda has also been effective.
Better planning tools. Athletes look at elevation, headwind, tailwind and will plan a strategy around going harder into the hard stuff and knowing when they can back off and rest.
And to be honest, probably a metric tonne of PEDs (performance enhancing drugs) - unfortunately this is very common across all sports at the top level.
Note that Sawe funded extra testing drug testing for himself for the 2 months before winning the Berlin marathon. The testing followed Athletics Integrity Unit protocols (so surprise testing etc):
https://www.letsrun.com/news/2026/04/how-sabastian-sawe-conv...
This seems unlikely to be true, although it is repeated in every article I read about carbon plated shoes. The people that study them in a lab environment seem to disagree. See some of the papers here:
https://www.wouterhoogkamer.com/science2
However, I agree wholeheartedly with the overall points in your post!
I’m guessing like most things of this nature, you’re likely to have super-responders, responders and non-responders?
Also interestingly, the shoe in this record uses much less carbon than past shoes, both saving weight and allowing even more super foam where much of the energy return comes from. Though there so much variance in shoe design and materials there are only theories on how much comes from the plate vs foam vs stack height vs weight vs other factors.
I wonder where that leaves the barefoot movement. Hype dust?
If I'm going bouldering I absolutely cram my toes into a tiny rock climbing shoe, because it allows me to stand on ledges I couldn't without the extra support from the shoe.
That being said, if barefoot generally feels good to you and you're not chasing the pinacle of performance it's probably a perfectly fine choice for your recreational runs.
The carbon plate revolution is the main driver for drop in times over the last 5+ years
If this were a bodybuilding discussion, you would get advice on how to manage DOMS symptoms and how to plan your loading schedule, nobody would say that weightlifting "doesn't work" because a beginner got sore after lifting a 80kg barbell for the first time. But people has been conditioned to think that running is a purely cardio activity, so we don't talk about how the muscles and tendons in the foot need to be loaded up gradually just like your bicep.
Barefoot running is a weightlifting activity. Your calf muscle has to lift your entire bodyweight for the forefoot stride. "No pain no gain" applies. Proper posture and techniques are important. Proper workout schedule and loading plan with rest days are important. Sufficient protein intake are important.
Why is going harder in the hard stuff and easier in the easy stuff more efficient or faster than vice versa? I imagine arguments either way:
Going harder when it's easy gives you higher ROI. Or maybe going easier when it's hard is just too slow. And maybe that is too simplistic: Maybe it depends on how hard; that is, maybe there is a threshold.
https://news.adidas.com/sabastian-sawe---london-marathon/a/0...
In his marathon debut too.
I wouldn't have predicted this out of nowhere, but if you told me a marathon debut went this well and asked me to guess whose it was, I like to think I'd have come up with Kejelcha in my top few picks.
That said, great 5000/10000 athletes don't always have great marathon careers. An example from this race is the world record holder at both those distances, Joshua Cheptegei. He's run several marathons but none spectacular by his standards. He was in this race too but 7 minutes back.
Based on the quote below, next thing we will see is a "constructors championship" similar to F1 for winning shoe constructor in the 'major' marathons :-(.
" This dominance continued in 2024, with adidas athletes wearing Adizero models winning six out of 12 World Major Marathons – more than any other brand."
and yes, of course i race in super shoes :-).
There are age group leaders as well. That's perhaps a hundred people, of the tens of thousands running next to me.
Marathons are about running my own pace. The fact that there exists a world record is a piece of trivia.
Of course innovation in shoes will have a bigger marginal impact (because physics).
Three athletes broke the men's world record. One athlete broke the women's world record, and three were in the all time top 5. An Irish record was also broken, likely other countries too that I'm not familiar with.
Not to take anything away from the achievements. Incredible running.
Not so. She broke a record for a female-only-pacer marathon time. The women's world record was much, much faster.
However, because marathon are often mixed gender and the best male runners are significantly faster than the best female runners, it is possible for a woman to be paced from the gun to the tape by a male runner. For this reason, there are separate records for the women's marathon for women's only events.
[0] This is one of the things that made Kipchoge's original sub 2 result not record-eligible.
She broke the thing that the IAAF have gone back and forth on calling "the world record". It's the relevant record for this event - there was no more chance of her beating the man-paced record than of beating the men's record or the Le Mans lap record.
Very few mere mortals could run that fast for even 100m.
That works out to roughly a 16.7-second 100m. While certainly not crawling, that would be a fairly average pace for a fairly fit middle- to early-high-schooler with a bit of practice.
Yes that’s insane to maintain for a marathon, but it’s not even remotely out of reach for 100m for most relatively-fit people at some point in their lives.
At my peak, I finished the NYC Marathon in the top 2%. I still finished 45 minutes behind the winner.
It feels like elite athletes aren’t even competing in the same sport.
https://www.athletic.net/team/770/track-and-field-outdoor/20...
* of course one mile is hardly comparable to the marathon that pros are able to sustain such speeds over...
https://www.athletic.net/TrackAndField/rankings/list/168546/...
That gives us 125k high schoolers in the USA who can break 04:30 for 1600m. There are about 18M high school students. So of just the high school population alone, about 0.7% of them can do this.
Assuming there are the 4x as many adults that can do this as there are high school students, that gives us slightly less than 0.2% of the total US population capable of this.
I rest my case.
Also bear in mind running a single mile under 4 mins was considered impossible for a long time.
It’s totally remarkable.
The big improvement then was a carbon plate. Adidas (and others) followed suit. The subsequent improvements since then have been marginal but the margins are thin at that level. In this case the big advancement has been the weight of the shoe.
EDIT: Also it's worth noting these shoes are $500 retail. Adidas will for sure get a boost in sales from this, but there's definitely competition in the $200~$300 marathon running shoe space that won't solely draw everyone to Adidas)
I think the big story here may be the nutrition science to get these guys to absorb a lot of carbs during the run, more than the shoes.
Essentially the argument given was too much advantage came from the shoes and they didn't want racing to be about shoe technology development.
The advancements in shoes have made a measurable impact, but there are lots of optimizations being worked on.
But yeah at this point, “it’s the shoes, stupid” should defo be the main part of the conversation.
Or did the AI say we should be using PVA/cyanoacrylate/polyurethane glue or something?
Was there perfect conditions.or something?
Insane you could run 1:59:41 and not win!
Sabastian Sawe 1:59:30
Yomif Kejelcha 1:59:41
Jacob Kiplimo 2:00:28
The previous official record was Kelvin Kiptum's time of 2:00:35 in 2023. Eliud Kipchoge did 1:59:40 in 2019, but that wasn't record-eligible as it was held under controlled conditions. Source: The article.
It does sound like the course and the weather made it more likely to happen. And technical advances in shoe composition.
> The leading men went through halfway in 60 minutes and 29 seconds: fast but not exceptionally so. But it turned out that Sawe was merely warming up.
Between 30 and 35 kilometres, Sawe and Kejelcha ran a stunning 13:54 for 5km to see off Kiplimo. Yet, staggeringly, more was to come as the pair covered kilometres 35 to 40 in 13:42. To put this into context, that time is two seconds faster than the 5km parkrun world record, set by the Irish international Nick Griggs.
It was only after a 24th mile, run in 4:12, that Kejelcha wilted. But still Sawe kept going. Astonishingly, he crossed the line having run the second half in just over 59 minutes.
“Before 41 kilometres, I’m enjoying, I’m relaxed,” said Kejelcha, who had won silver over 10,000m at last year’s world championships.
“My body is all great. At exactly 41 kilometres, my body stopped. I tried to push, but my legs were done.
Sawe, though, powered on to set the fastest official marathon time in history. For good measure, it was also 10 seconds faster than Eliud Kipchoge’s unofficial 26.2 mile best, set in Vienna in 2019.
https://www.theguardian.com/sport/2026/apr/26/sabastian-sawe...
5km - 14:14 10km - 28:35 15km - 43:10 20km - 57:21 Half - 60:29 25km - 71:41 30km - 1:26:03 35km - 1:39:57 40km - 1:53:39 Finish - 1:59:30
Yomif Kejelcha also ran sub-two, clocking 1:59:41 on his debut marathon
You have to feel for Kejelcha - breaking 2h marathon and not even winning the race!
- https://www.mdpi.com/2813-0413/5/1/2
This is a nice video of the last 10 mins of the historic marathon race finish
London is a fast course. Let’s see what happens in Chicago and Berlin. If it was primarily tech that did it, we should see the record fall again.
Endurance sports are quite accessible and don't require that much time, effort, or talent to get way better than the vast majority of people, it's just consistency.
FWIW, that now includes me, as a 62 year old. I can hit 6:30 pace for 400m, but find it almost impossible to get under 10:0x for a mile. And that's even after 6 months of training for a 50 mile trail race.
It would be interesting to adjust this speed to account for the insane advancements in shoe technology over the last decade. Could it be as simple as measuring the delta in median marathon performance? Then look backwards to, say, 1996 and see what the technology-adjusted 2:00 mark is.
Sub-2hr marathon, beat the previous world record before Sunday, on your first try, and you don't win! Bad timing...
Prize money for London Marathon 2026 - https://www.thesun.co.uk/sport/38880592/london-marathon-2026...
Looks like first place male gets US$330K. Second place will get US$180K.
Divide by 2 to get the approximate hourly rate. :)
There's been lots of research into shoes though, so you might be able to work something out. For instance Jack Daniels (the running coach, not the beverage!) found that adding 100 grams to a running shoe increased aerobic effort by around 1%.
The popularity of running waxes and wanes - and the performance of the median runner varies with popularity.
Back in the 1980s the average half marathon finishing time was 1 hour 40 minutes - whereas today it's a little above 2 hours because there are a lot more people particpating.
Amazing these guys did it in a real race with no one in front of them (at the end at least)
I used to love F1 for the tech that would filter down to my car in ten years time, but that is not a thing anymore.
I for one love the advances in technology in something as supposedly simple as a shoe. And maybe I'll get to use it on a hike in a few years.
These shoes are practically disposable. They trade longevity for noticeable gains in performance. Even the tier below don’t last very long. This is not tech that is going to filter down to your hiking boots.
But the initial tech on an F1 car was not made for 200k miles either.
Even if the full tech stack to make it all work - material science, physical layout and construction - doesn't transfer, maybe some bit of it will.
My point being though, unlike some purists, I like the technology race. It is much better than having a brand war simply on the basis of brand loyalty.
Also it must be an crazy feeling to be Kejelcha, the guy who came in 2nd place. It would have been a world record, except for Sawe!
Besides weather, there are loads of factors in the performance: shoes, clothes, food, etc. So basically every record gets an asterisk?
There is no rule for marathons.
I thought there were scientists on here...
Don’t forget that two people actually ran under the two hour mark.
Obviously, barring wind, which is why some marathon courses are not eligible for world records.
It should be.
By contrast, hail/rain and wind will negatively impact almost everyone, which is why talking about "a bad weather day" makes more sense.
https://marathonhandbook.com/large-scale-marathon-study-iden...
I just said it needs an asterisk, not withholding anything. What if someone runs one second slower in higher humidity and temperature. Now that I would applaud.
It’s essentially the same as not setting the record. It would be qualified every single time it’s mentioned and be functionally saying “…so it doesn’t count.”
Edit: I was thinking in km/h and mixed it up. Sorry.