Comment by nikcub
17 hours ago
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
> 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.
> 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.
Exogenous carbohydrate doesn't spare muscle glycogen, only liver glycogen.
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).
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...
https://archive.ph/Vpk0h
https://pmc.ncbi.nlm.nih.gov/articles/PMC9560939/
That may still be worthwhile if fat is harder to recruit than exogenous carbs.
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?
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.
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 ;-)
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!
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.
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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.
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!
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.
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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.
> 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 ?
> 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.
> Third, his steroid/peds program is on point and his body is responding well to it.
Do you have any evidence of this?
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.
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.
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.
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We never had any for Lance Armstrong until he confessed.
> 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.
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.
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
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.
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.
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...
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.
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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.
They're equivalent modulo some multiple. It doesn't matter which one we talk about, as long as we're consistent.
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
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.)
Yeah, I assume this dumbification is spearheaded by the Americans.
It's deliberate, because you generally do not want calories from fat or protein during a marathon or other running race.
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.
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.
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.
it is a lot more challenging when running than when biking. The jostling is not your friend.
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.
The leaders were burning a lot more than 100kcal per hour. I think you mean 100g of carbohydrates per hour.
Not burning, eating. They are eating 100g of carb per hour. Burning 1000+ calories.
Re [0] how do they measure this reliably during a race, especially the C-isotopes in the breath?
From the picture it looks like he is only wearing a watch and there is perhaps a little bulge on his left side.
They collected samples every 5k in the 30k long run before the marathon, see Substrate section in http://athlete.maurten.com/
Correction: 100g of carbohydrate/hr. That's approximately 400 calories/hr.
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).
Pro cycling has been on the high fueling strategy for a while, with huge results for record times. Its a game changer for endurance sports.
Can someone explain this in more details? Like will you run out of energy, your result will suffer drastically, anything else?
The reason I am asking - I hike a lot, and for shorter hikes (<35km) I don't even bother with food. Just last Saturday I did 28km hike with 550m elevation gain - last meal I had was 5pm on Friday. No breakfast. No problem. I walk at a brisk (for layman) pace, ~7±2 km/h. Am I missing something by not caring about food there, or for my level of "performance" it does not matter anyway? The original question still stands.
Your muscles need energy to work. You have a variety of energy stores in your body, which range from small amounts of quickly available energy (ATP) to large amounts of slowly available energy (fat). Most relevant to this discussion is glycogen, which is is a carbohydrate. You have about 500g in your body, which is about 2000kcal. It is more readily accessible than fat, and 2000kcal is enough for an hour, or maybe two, of high intensity exercise.
These gels and drinks are trying to replenish glycogen stores. The idea is to keep the runner using glycogen for the entire race, as it provides more energy per unit time than fat metabolism.
In your hikes your energy demands probably aren't exceeding the rate that your fat metabolism can provide.
I'm not an expert, so do some research, but it's probably a bit of a) you've trained yourself to burn fat more (a good thing) b) you're not exercising as strenously c) yes, if you ate you'd probably "perform better".
I'd recommend you to do your own research though.
But to add - yes, if you don't eat you will "bonk" on a long bike ride.
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100 g of carbs is 400 calories, not 100.
> 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]
In trail running especially it's not uncommon to exceed the recommendation of 1g/Kg bodyweight/hour, up to 120g of carbs per hour, for those that can take it.
Do we know of any adverse effects on such long term consumption of that amount of simplest carbs? While good source of immediate energy, simple carbs are basically a slow acting poison to various internal organs and over time bring stuff like diabetes.
Its great they don't sit idly around in the body and get transformed into fat but rather they are burned in muscles, but still flooding body again and again with this may have long term negative effects that far outweigh any health gains gained from doing these sports, even at such intensity.
Definitely not a diet one could recommend for regular sporty guys, unless they are uber-competitive freaks who have to win at all costs.
> simple carbs are basically a slow acting poison to various internal organs and over time bring stuff like diabetes.
Do you have any evidence for this? The problem with simple carbs (if you don’t already have insulin issues) is that they’re easy to digest and provide minimal satiety so you end up consuming significant calories.
But as far as I’m aware there is no evidence that they’re worse for you than the rapid calorie addition.
These athletes are eating nutritionally complete diets overall. The simple carb intake is a strategy just for the run itself.
That said, pretty much everything about highest-end athletics is net negative for long-term health. It’s incredibly hard on the body to run a marathon in general, let alone at record breaking pace.
I don’t think there is any elite level sport that doesn’t trade long term health for performance in competitions.
Adidas all over this one https://news.adidas.com/running/two-adidas-athletes-sabastia...
The Adidas Adios Pro Evo 3 - https://news.adidas.com/running/adidas-unveils-its-first-sub...
For other marathon racing shoes, Google says:
You can buy them in the UK soon, just £450 and I suspect they'll disintegrate quickly... https://www.adidas.co.uk/adizero-adios-pro-evo-3-shoes/KH767...
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Which is why this feels so artificial and why it’s the 3rd most read article on the front page of the FT. Running as a sport has been very sadly and irremediably gentrified, gone are the days of Zatopek and of Abebe Bikila winning an Olympic marathon barefooted. Fuck Ineos and its owner, too, while I’m at it.