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nikcub
Stunning results at the top of the field. Some interesting takeaways on both fuelling and shoes.
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
PaulDavisThe1st
> could absorb and burn 100 calories per hour
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.
loeg
> burning a hundred calories
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.
andreareina
Exogenous carbohydrate doesn't spare muscle glycogen, only liver glycogen.
wging
I've read that even if you absorb it all, there's some question about whether it's useful. This Alex Hutchinson article suggests, among other things, that it may spare your fat stores rather than your muscle glycogen:
> 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...
loeg
That may still be worthwhile if fat is harder to recruit than exogenous carbs.
Earw0rm
Kejelcha is 6'1" and under 130lb.
What fat stores?
gield
The last few years, cycling and triathlon have been experimenting with upto 120g carbs intake per hour. Last year, Cameron Wurf ate 200g carbs per hour when he broke the world record for fastest bike split ever in a triathlon (which was broken again a few months later).
canucker2016
a 2025 look at elite triathletes fueling at https://www.triathlete.com/nutrition/race-fueling/ironman-wo... shows that norwegian athletes are ingesting higher amounts of carbs (~180g/hr bike, ~120g/hr run - 2 males, ~150g/hr both run & bike - 1 female) especially for the bike portion.
bethekind
Where does discussion on gut training occur? All I know is you need a 5:4 ratio of glucose to fructose? Then when you train, you use the gels and the more you do it, the more capable your gut gets at absorbing without distress.
Is that all the science to it?
andreareina
AFAIK 5:4 is just the lowest ratio they've tested. Personally I use table sugar (1:1) and can sustain rates above 100g/h. Haven't hit the ceiling yet, don't really feel the need to explore where that is yet because exceeding the absorption rate comes with the risk of diarrhoea which is bad at any time but especially when you're in the middle of a training session and who knows where the nearest toilet is.
Gut training is consuming large amounts of carbohydrate (preferably in the same form you intend to use when racing), yes.
scott_w
Yes but the science is actually achieving that and finding the limits. It used to be thought that 60g carbs/hour was the limit, then 100g, now it’s thought to be 120g.
It’s also about the methods of achieving that under stress without spewing it all back up. Ironman athletes would stuff their faces on the bike under the assumption that this volume of carb absorption wasn’t possible while running.
Some of the challenge in research will come from competitors not wanting to publish results to maintain an edge. It is mitigated by the visual of the race by (you can see athletes pounding carbs), as well as the nutrition companies wanting to sell more product. This will cause them to publish some information to convince us amateurs to quadruple our purchase volume ;-)
chongli
Wow so he was absorbing 400 calories per hour with this gel, but he was likely burning 3-4x that amount (or even more) while running 13.1 miles per hour!
brianwawok
In a two hour race that’s still 800 bonus calories, that’s something.
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.
almost_usual
Your body stores roughly 2000 calories in glycogen. They are burning calories but nowhere near the amount a middle pack would be at this pace.
So ~2800 calories of carbs with some fat being burned.
aitchnyu
What are the long term effects of a lot of processed carbs on the gut?
alfiedotwtf
Is there anything here a people who should be dieting could learn here? I’ve found when running, every 3-4km if I do t have sugars/gatorade my blood sugar gets so low I end up almost confused… running suburban streets is tough because I’ve got to cross the road when I’m midly delirious!
Earw0rm
How far are you running total, both per run and per week?
Running will absolutely help your health, but on its own it's unlikely to get you thin. It's hard to burn enough to make a big difference without it chewing your body up in other ways - especially if you're overweight and out of condition to begin with, and so a bit more susceptible to injury than skinny runner types.
Thinking of it as a calories in/out equation is counterproductive for most people, if it boosts your cardio health, gets you more active and maybe converts a bit of body fat to leg muscle, that on its own is a win.
Certainly no harm in having a swig of Gatorade every couple of km if it helps you go further, anyhow.
KeplerBoy
I guess it's the classic case of one not being able to outrun a bad diet.
If fueling during the activity stops you from overeating afterwards and possibly allows you to exercise a bit longer it is worth it, even though it seems counter productive.
groggo
One gram of carbs is 4 calories., so more like 400 calories per hour.
It was confusing when the running industry switched from calories to grams of carbs, but that's all anyone talks about now.
mbesto
Because calories simply do not matter. At high intensities of working out, it's the amount of carbohydrates you can consume that allow more fuel to be burnt.
"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...
fc417fc802
Calories do matter (obviously, as energy intake is the entire point) but as you note the specific form that the fuel takes matters. However "carbs" is a catch all that includes plenty of things that (I assume) would be of similarly minimal use in this scenario. The calories need to take a very specific chemical form for this to work.
teiferer
Then why replace one imprecise term with another? Fiber is a carbohydrate. Humans use close to nothing from its energy. (Though it plays another important role in the digesive system.)
Try eating 100g of grass per hour during a marathon and you will see. That's the metabolic edge horses have over humans.
loeg
They're equivalent modulo some multiple. It doesn't matter which one we talk about, as long as we're consistent.
whycome
It’s also confusing that most nutritional labels say “calories” (Cal) when they really mean kilocalories (kcal). And those are different from regular (‘small’) calories (a measure of energy needed to heat 1g water 1c).
1 food calorie as listed on a food label is enough to heat 1kg of water by 1c
schoen
This was the explanation for why the scotch and soda diet doesn't work:
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.)
estomagordo
Yeah, I assume this dumbification is spearheaded by the Americans.
justinwp
It's deliberate, because you generally do not want calories from fat or protein during a marathon or other running race.
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aucisson_masque
> 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.
That common knowledge, nothing revolutionary here.
There are 2 types of sugar, fructose and glucose, you can max out on glucose around 60g/hour and train you guts to max out also on fucose.
Personally I reached 90g/hour without training, no diarrhea or vomiting.
And you know the best ? White sugar in everyone kitchen is almost perfectly 50% glucose, 50% fructose.
You don't need 'advanced' gel to do that, a bottle of water with 120g of white sugar an hour.
And the shoes, yeah they're light but guess what. Other competitors also have sponsors and excellent shoes, some even run bare feet and yet they don't go faster.
No the real reason why he is able to run so fast is first excellent genetic, that's the common base.
Secondly, excellent training, coaching.
Third, his steroid/peds program is on point and his body is responding well to it.
Typically for endurance runner you want profiles with low natural hematocrit so you can max out on the EPO, but there are also other considerations. For instance, are his tendons responding well to GH and other peptides ?
pfix
> That common knowledge, nothing revolutionary here.
I've never read about that. So it's not "common knowledge" - except maybe in the running community.
I like your comment for putting some facts into place (how far you can go with common options). But as I never heard of this before, I have no idea how common it actually is and the effects and the science around it, what research does say to this, how and why this is used in other sports - or why not.
aembleton
> You don't need 'advanced' gel to do that, a bottle of water with 120g of white sugar an hour.
Did you carry all of these bottles on a marathon? Did you have to stop to get them out of your bag? How did you find drinking whilst running?
I find gels much more compact and for the amount of time I need to run one - over 4 hours there's a lot of weight I need to carry. I can store a lot of them up front in my running vest and keep going.
ragazzina
> Third, his steroid/peds program is on point and his body is responding well to it.
Do you have any evidence of this?
klooney
There are two kinds of athletes that win global track events: - athletes from areas with bad doping enforcement (remote places in the mountains of Kenya, Jamaica) - athletes from countries with tons of surplus biomedical expertise (USA and other western countries)
ap99
His comment is more of a general commentary that east African countries are notorious for doping.
Like, if we find out the top two finishers here doped very few would be surprised.
That said - it's still an amazing accomplishment.
LanceH
It pains me that running, track, and cycling are "notorious" for doping, but the major sports don't test at any practical level compared to the "dirty" sports.
m348e912
I have no evidence of this at all. I did thing it was interesting the demeanor of Sebastian Sawe and second place finisher Yomif Kejelcha, both of whom finished under 2 hours.
If you watch Kelvin Kiptum break the world record at the 2023 Chicago Marathon and Eluid Kipchoge break the world record in the 2022 Berlin Marathon, you see the joy and exasperation of their achievement.
That joy was missing in the winners of the London marathon. It's not evidence, but it's an interesting data point. Another data point: Not only did the first two finishers break two hours, the third place finisher, Jacob Kiplimo, broke the world record.
gadders
We never had any for Lance Armstrong until he confessed.
boringg
Pushing up to and over 100 is the challenge. If i remember right 90 is 60-30 (gluc and fruc) and the upper limit after that GI distress.
You a cyclist or have you been doing that from running?
From homemade concoctions… you can use maltodextrin for pure glucose.
whycome
> The hydrogel technology they have developed
At what point is this just a performance enhancing “drug” — what makes something a drug?
zackify
I agree with you. I used maurten 160, 320, and the gels years ago.
Now I just throw honey into water on my runs.
It doesn't upset me even though maurten does feel a little better, its worth saving tons of money over buying maurten
_blk
I'm not the expert on the bio but the gel has the advantage of being consumable while running. Try drinking while running. Even at a slower pace it's hard not to spill. If you want the dosage correct you can't spill.
tedggh
I normally consume 90g of carbs per hour when long distance biking, so do a few other riders I know. No GI issues. I use Skratch some other guys like Precision.
dogmatism
Yeah, I just literally use table sugar, which is 1:1 glucose:fructose. Maurten et al using 1:0.8, close enough! And I don't believe the hydrogel thing is any magic, just marketing.
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.
chantepierre
The hydrogel textures (not maurten but naak, but close enough), for me, allow while racing to swallow a full 40g gel in half a second without feeling the sugary taste a lot, which is nice. Compared to thick syrup-like gels, it’s a way better experience in a marathon.
But I only buy for actual races, rest of the time, I do my own 1:0.8 mix with a bit of thickener, in soft flasks. Much more cost effective.
rpearl
it is a lot more challenging when running than when biking. The jostling is not your friend.
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bluecalm
It's much easier when cycling and there is much more freedom with your breakfast choice and timing. You are stable on the bike. When running there are constant vibrations and up and down movement that can easily upset your stomach/intestines.
boringg
In terms of getting to higher caloric loading due to gut system restraints. It sounds like running has finally caught on to what professional cycling has been doing over the last couple years. Bodies ability to handle high caloric loading is the rate limiting step.
nradov
The leaders were burning a lot more than 100kcal per hour. I think you mean 100g of carbohydrates per hour.
brianwawok
Not burning, eating. They are eating 100g of carb per hour. Burning 1000+ calories.
ekr____
Correction: 100g of carbohydrate/hr. That's approximately 400 calories/hr.
bluecalm
Race day super shoes certainly help a lot but another difference is that super shoes allow them to train a lot more. Running training is limited by tendons. This is the reason even elite runners often train only 9-11 hours a week while many dedicated amateurs can easily spend 20+ hours per week cycling. This is also the main reason runners "double" that is they run 2 times a day. The body absorbs 2x45 minute session much better than one 1x90 minutes session.
Super shoes are changing the game here allowing for more volume for months without injuries. When you look at Sawe's training his volume is insane. His easy/endurance days are 20km in the morning and 10km in the evening. This is some 100-110 minutes of running on "easy" days. His total time on feet must be around 14-15 hours per week - approaching cycling volume territory (especially when you consider that cyclists do significant % of their volume cruising/descending without putting almost any power at all which inflates the time).
signorovitch
Feel a bit bad for Yomif Kejelcha who also broke the 2-hour mark, with this being his first competition marathon, but managed to neither break a record nor win.
glenngillen
But he has the best average time of any competitor in the history of the event! ;)
nerdsniper
3rd place runner also set a new world record, but just didn't break the 2-hour barrier.
darth_avocado
While I know competitors want to always strive to be the best, as a completely normal human who struggles to complete a half marathon under two hours, I do not feel bad for the guy. He’s still one of the only two people to do it (outside of the very controlled run from Kipchoge). Not a feat to feel bad about at all.
cflewis
The majority of people in the world cannot complete a half marathon, let alone under two hours. I was pleased to train enough that I managed under three. You're doing great!
BrandoElFollito
A majority of people won't run 1 km without needing a rest afterwards.
There were recent tests (in France I think) in schools where 50% or something could not run 1 km (sorry I don't have the details on mobile). These are children who have infinity energy (source: parent).
A typical adult won't make it to 1km (source: going back to sport and dying on a 2.5 km run)
gregdeon
Sub 3 is incredible, congrats!
sayamqazi
half marathon is ~20 KM its pretty sad that a large percentage of people cant do that. One can simply walk that much distance wihtout any prior training.
potamic
There is the silver medal syndrome.
Aurornis
I'll admit I'm not familiar with running, but in other sports it's not uncommon for amazing early career athletes to hold back a little bit on their first attempts.
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.
parsimo2010
While that seems like a bummer, as long as he doesn't quit he'll have many more chances to set the record himself.
MengerSponge
Real "Bad Luck Brian" energy
dyauspitr
[dead]
vessenes
Don’t forget Yomif Kejelcha who finished in 1:59:41, a world record up until 11 seconds prior. Amazing.
curt15
> Don’t forget Yomif Kejelcha who finished in 1:59:41, a world record up until 11 seconds prior. Amazing.
In his marathon debut too.
giarc
I read that as well... how could it be his first marathon? Or is it his first "big" marathon?
wging
It's his first marathon ever, but he's a very experienced runner. It would be hard to find a better prospect for a good first marathon. He's a multiple (former) world record holder and medalist at shorter distances from the mile up to half marathon. His half marathon is still 2nd all time.
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.
ronbenton
Imagine having the second fastest marathon time ever yet not winning the marathon you ran it in
twobitshifter
Apparently 3 people broke the record in the same race!
spenjovewkwhalo
Posted to my in-laws, who asked how:
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.
nl
> probably a metric tonne of PEDs (performance enhancing drugs)
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...
rao-v
This is news to me and genuinely impressive. Putting extra work into ensuring your attempt at one of the few records that will last the duration of humanity is damn smart.
e44858
Drug testing has its loopholes: https://www.npr.org/sections/thetorch/2016/07/19/486595080/r...
nl
Yes it does.
Pretty hard to use the in-competition avoidance strategy like that in this out of competition case though.
k2enemy
> Most shoes have carbon plates in them now, they act as a spring, storing energy and propelling athletes forwards.
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!
spenjovewkwhalo
Ooooh, interesting- I’ll take a read, thanks!
I’m guessing like most things of this nature, you’re likely to have super-responders, responders and non-responders?
nickcoury
Yes, most of the studies show there is a very large individual variation. The original 4% figure and similar studies were an average of something like 1-7% across runners.
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.
giarc
Maybe even placebo effect?
twobitshifter
Well at least on the PED front, saw has been doing an extreme amount of testing to try to eliminate those doubts.
shusaku
> Better understanding of fuelling. … Better planning tools.
When I was young everyone acted like running was all about who could endure misery the longest. I think if I had known about these aspects it would’ve seemed more strategic and interesting (especially with smart phones to help). Alas, these days all my effort is in making sure my run doesn’t kill my knees :\
tejohnso
> Super shoes. Most shoes have carbon plates in them now, they act as a spring, storing energy and propelling athletes forwards.
I wonder where that leaves the barefoot movement. Hype dust?
riknos314
As a 16 year wearer of mostly barefoot shoes, "barefoot" for me is about comfort in general day to day activity. It isn't a specialized tool and certainly isn't the obvious choice for extreme environments.
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.
dogmatism
No competitive distance runner since like Zola Budd ran barefoot or minimal shoes.
The carbon plate revolution is the main driver for drop in times over the last 5+ years
ungreased0675
I’d consider the old models of Nike Waffle race flats pretty minimal, and those were ubiquitous 15-20 years ago.
ungreased0675
I still prefer to run in minimalist shoes because I like to feel the ground. The new breed of running shoes seem comically thick to me. I tried a pair for a few weeks, they still feel wrong. If a company would make a low stack height shoe with one of the new super foams, I’d probably buy three.
brewdad
Was the barefoot movement ever about running faster? I always thought they sold injury prevention by strengthening tissues that running shoes tend to over support.
nradov
Yes, that was the claim but it was never really backed by evidence. Vibram settled a lawsuit over false claims that their minimalist shoes reduced the risk of injuries. (I still like those shoes myself and use them on some slow recovery runs.)
benhurmarcel
They never claimed it was faster, but healthier
xutopia
Heat training does much of what EPO used to do. It's amazing how much science has caught up in this field.
xarope
the consensus seems to be that the foam itself is the spring (hence the successful adidas evo sl and dynafish xiaonian), and the carbon plate/rod/whatever is more to control/manage that "spring".
mmooss
> going harder into the hard stuff and knowing when they can back off and rest.
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.
bigiain
Completely uninformed speculation:
Wind drag goes up with v squared, so power required goes up with v cubed.
If you run at 105% speed downhill,that requires almost 16% more power to overcome wind drag. You might be better off running at 100% speed downhill (and "saving" that 16% power), and pushing harder to run as close as you can to 100% speed on the uphill stretches that would otherwise have you running slower than 100%. The power used to increase your potential energy going uphill is "zero sum" because you get it back when you go back downhill -n there no pesky v squared or v cubed non linearity there (assuming the race starts and finishes at the same elevation).
rich_sasha
A fun little effect is that average speed is time-averaged not distance-averaged. So when you go slower, you lose doubly - lower speed to average and over a longer time (higher weight). Hence one of the reasons why putting more energy into the harder bits is actually optimal.
bbcc90
I'm a runner, and it's a bit sad that distance running is not longer purely about the runner.
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 :-).
jfengel
The winner is doing a completely different sport from me. I never even see the winners at a marathon. They are long gone by the time I get to the start line, and they've gone home by the time I finish.
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.
aembleton
> Marathons are about running my own pace. The fact that there exists a world record is a piece of trivia.
I do find the record fascinating. If I take the 5k, 10k and half-marathon world records and double them then I can run faster than that. But for the marathon I'm a long way off. There's something uniquely difficult about it because it's not just going for a run, but fuelling and training your gut and pacing. I've only done 2 marathons, but I do find them uniquely difficult so for me its extra special to see how fast a human can do it in.
nerder92
It was never about the runner, it has always been about technology and innovation. Shoes tech is just one of them. Better nutrition, novel training techniques, better air quality etc.
Of course innovation in shoes will have a bigger marginal impact (because physics).
jampekka
Can't help but think that the wins and records done barefoot and without refreshments in the 1960s are still a bit more about the runner than running with essentially spring loaded shoes, lab-optimized nutrition gels, computer optimized pacing strategies and multisensor real-time measurement devices.
It's also somewhat ironic for a race supposedly modeling a messenger running the distance in an emergency situation.
Ekaros
Also makes wonder question did the messenger participate in hard cardio training before. Meaning the fighting. Or do some messengering before.
bbcc90
For sure but most of that innovation pre-super shoes was optimizing the runner, not the shoes
foxglacier
Of course it's also about the runner, that's why the Kenyan models dominate with their biological innovation.
dmurray
There's something about the London course today that made for very good running.
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.
PaulDavisThe1st
> One athlete broke the women's world record
Not so. She broke a record for a female-only-pacer marathon time. The women's world record was much, much faster.
ekr____
To add some color here: It is very helpful to have someone pace you so that you can run an ideal pace without worrying about whether you are running the right speed. However, the rules require that pacers start with you [0], which means that by definition if you are running faster than anyone has ever gone before you have to run some of the race alone.
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.
ungreased0675
Having a pacer start with you seems to defeat the purpose? I’d prefer someone fresh and full of energy to jump in halfway to carry me through the end.
dmurray
I stand corrected, but I don't think this changes my point at all.
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.
NooneAtAll3
what does female-only-pacer even mean?
PaulDavisThe1st
It is common in "big" marathons for the fastest runners to have pacers with them who help establish and keep a pace. They could be male or female, but the fastest marathon runners are generally male, so they tend to be male. "Female-only-pacer" means that only female pacers are used.
rhplus
Is there also something beneficial about the shirt he wore? It has a unique embossed pattern on the chest. Is it just a nice design or does it also provide aerodynamic or heat wicking advantage?
https://news.adidas.com/sabastian-sawe---london-marathon/a/0...
cevn
I can sort of visualize an aero improvement. If wind hits you flat on it goes all around and right against you, and it can bump into itself and then back on you since it's almost directionless. However if you have 'needles' coming out it gives the wind a 'direction' other than straight at you, lessening the pressure against your front.
double0jimb0
Good eye! Almost like an inverted golf ball. If I remember correctly from undergrad aero, purpose of dimples on golf ball is to detach/disrupt more of any laminar flow earlier as air passes around the ball, which decreases drag. Golf balls travel way faster than a runner, but possibly still has some minor effect?
huflungdung
[dead]
cowthulhu
Wow, that’s ~13 mph, basically a full-on sprint for a mere mortal. Absolutely insane.
PaulDavisThe1st
The fastest marathoners are moving at 4m30sec per mile or faster.
Very few mere mortals could run that fast for even 100m.
jmb99
> 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.
PaulDavisThe1st
It's the "at some point in their lives" that matters here. For most folks, the period where a 16.7 100m is feasible is pretty short.
croemer
I think it's even slow for high schoolers. I didn't practice that much and ran 100m in 12.5s from rest at my peak. 4s slower is snail pace. I think most in my class could run that fast (or slow).
ecshafer
I ran a 16s 100m in highschool.... as a thrower, and was very slow. The 100m dash with the fast people was like 12s.
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petepete
There's an interesting video by Mark Lewis on this.
hackingonempty
Here's a random high school in Northern California. Everyone on the team is beating 16.7 seconds in the 100m. For the 1600m there are six kids with times under 4m30s and another seven with times under 4m40s, all in the last month.
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...
sethev
Not sure that disproves the point :) Most people have never been anywhere close to competing with the top 6 athletes at a high school with ~2k students.
hyperpape
Unless kids have gotten a lot faster in the past 25 years, I think that's a lot better than a typical 2000 person high school.
PaulDavisThe1st
How many kids at the school?
malbs
The fastest 1km I ever ran was around 3m20s, I felt like I was sprinting, and was fully cooked at the finish line.
Afterwards I did some quick numbers and realised the average marathon runner was not only going a lot quicker than I was, but they were doing it for a further 41km
LanceH
You've proven you can run one kilometer. You just need to prove that if you run any km, you could run the next km, then you're done.
jonplackett
Sometimes they have big running machines with a crash mat around them running at 2h marathon pace at running shows. I’ve o ly seen them on video - no one can keep up with it for more than 30 odd seconds. It’s INSANE they are running this fast.
Also bear in mind running a single mile under 4 mins was considered impossible for a long time.
acomjean
We used to be amazed when I ran cross country in high school that these pro marathoners would best all of us in our approx 5K(3ish mile) races and then go on to repeat that distance multiple times.
It’s totally remarkable.
soupfordummies
Yeah I can barely even ride my bike that fast much less keep that pace for two hours.
fredley
He did his _last_ mile in 4.17. Insane.
mkl
21.19km/h on average, or 17 seconds per hundred metres on average.
croemer
No, it's slower than most people's sprints. It's 17 seconds per 100 metres which is slow. Most teenagers can do this starting from rest.
Cthulhu_
I'm not a runner at all, but people say that they can do that for like a minute, maybe two at best... and these guys did it for two hours straight.
ternaryoperator
And the only place this appears on ESPN is if you click on "Olympics," which has nothing to do with this race. Where coverage should be: on the home page.
conductr
It’s certainly noteworthy and interesting but I could see how Running as sport isn’t popular enough for front page. Especially during NBA and NHL playoffs, NFL draft, and whatever else might be going on.
timerol
This is the most significant record in running to fall since 1954 when a sub-4 minute mile was run. I think running can be front page news once a century
conductr
I get it and agree, but historical significance doesn’t factor into what they put on front page or what is popular at the moment. It’s not a slow news day for sports and they don’t think their viewers care enough. I’m sure if we had their data it would show us that they wouldn’t.
It’s not meant to be malicious they just don’t report on things that don’t get enough engagement. If you look at the long list of sports they cover, there’s nothing running related even mentioned. They do now have an article on it in their Olympics category as of 2 hours ago. But I feel like them not having a breaking news coverage on a Sunday in this sport is to be expected more so than your expectation of them covering it.
brewdad
If this happened at Chicago, it would be front page news. Boston and NY aren’t WR eligible. Since it happened in London, place it behind soccer in the priority list.
adverbly
Wait two runners beat it in the same race?
Was there perfect conditions.or something?
Insane you could run 1:59:41 and not win!
rkagerer
Three of them, actually:
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.
mkl
Two beat two hours is what they meant.
nradov
Weather and course conditions were good but not perfect. There is potential to take a few more seconds off the world record in slightly colder conditions and on a course with fewer turns. I wouldn't be surprised to see someone run 1:58 in the next few years.
ohyoutravel
This is probably right. We’ll also see at least five unique sub-2s before the end of 2027.
hdndjsbbs
Pacing is a big part of endurance sport. If you're in the lead you know intellectually you want to pace for sub-2 hours, but if you're watching someone beat you maybe it gives you the extra edge?
It does sound like the course and the weather made it more likely to happen. And technical advances in shoe composition.
PaulDavisThe1st
That's not a description of how the pacing for this race actually happened.
> 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...
brewdad
Elite marathon runners aim for a one minute negative split (Second half faster than the first). These guys pretty much nailed it.
jonplackett
These were Sabastian Sawe's splits
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!
codezero
Those shoes are gonna sell like crazy now but it would be hilarious if they were to be found to have been giving an unfair advantage because of some mechanical property of the shoe.
icegreentea2
Reviews say that they have very very good, but not record breaking energy return and shock absorption. But what they are is insanely light at sub 100g.
parsimo2010
For a while it was all about getting the lightest shoes, because picking up heavy shoes slowed you down. Then the energy return (pebax foam, carbon plates/rods) became the main focus because the weight didn't matter as much when the shoe was literally springy. Surely this is now going to spark a race for the optimal balance between weight and energy return.
tialaramex
I can absolutely imagine that the "correct" balance varies from one person to another, and yet that this is both measurable and also irrelevant for non-pro athletes.
Like the number one endurance runner in the world will get a minute off their marathon time because a shoe manufacturer spent $1M making custom shoes for that athlete which don't even have a size they're just "For this one specific person, now" but then some guy on Reddit wants better shoes because he's sure his four hour marathon would have been "more like three" if he had those elite shoes instead of the $100 Nikes he wore...
mbesto
The Nike Zoom Vaporfly's already had set this precedent years ago: https://www.nytimes.com/interactive/2018/07/18/upshot/nike-v...
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)
pclmulqdq
Do these new Adidas shoes have anything major over the Vaporfly shoes? Maybe they are a bit lighter?
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.
loloquwowndueo
Well if they’re sold in stores and next year everyone will have a pair, then it’s not going to be an unfair advantage, is it?
colechristensen
There is a whole class of running shoes banned from various competitions.
Essentially the argument given was too much advantage came from the shoes and they didn't want racing to be about shoe technology development.
sergiotapia
what else could it possibly be if not that?
robot_jesus
Well, the marathon record has been broken 53 times since the early 1900s. So, there are a lot of factors at play. Better training, better nutrition, better tactics, and, yes, better shoes.
The advancements in shoes have made a measurable impact, but there are lots of optimizations being worked on.
tialaramex
Also population and access. In the time since the early 1900s a lot more humans exist, and more of them have the opportunity to attempt this record. Population in Africa exploded in that time and access improved significantly.
If you're bloody quick and born in Birmingham (either of them) in 1900 you can probably find out about and get yourself a chance to attempt that world record, but if you're born in Kapsabet (in Kenya) in 1900 good luck, even in Nairobi I wouldn't bet on it.
jonplackett
There’s info in one of the other threads about better carb intake too.
But yeah at this point, “it’s the shoes, stupid” should defo be the main part of the conversation.
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DwnVoteHoneyPot
[flagged]
nearlyepic
If I wanted to know what an LLM thought (I don't) I would go ask an LLM.
MattCruikshank
One person sharing what an LLM thinks is probably better for the environment than each person asking...
kibibu
AI told us we should add glue to pizza
ray_v
In this economy, it may be sage advice.
_carbyau_
Is that not what tomato paste and/or cheese is? Food glue? The other ingredients would fall off too easily otherwise.
Or did the AI say we should be using PVA/cyanoacrylate/polyurethane glue or something?
dyauspitr
You should stop using 3.5
readthenotes1
I'm pretty sure that's an old trick based on some of the so-called cheese I've had on pizza
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