TrainingPeaks article 144 grams of carbs per hour

Anyone else read this article. It states studies show you can go up to 144 grams per hour at a 1 to 1 ratio. This is way different than the 90 per hour and 2 to 1 rule I have heard the most.

Nate feel free to time chime in as I know you love your carbs and at 100 an hour you maybe leaving 44 grams on the table lol

That’s a pretty poor quality article, IMO.

It starts off fine, until they claim with no evidence whatsoever that the common practice of 2:1 is wrong, and advocate for 1:1 again with no evidence or data. They also mention that you can’t exceed 60g with just glucose, and mention that you’ll want between 0.8:1 to 1:1 fructose:glucose, and then also recommend 144g carb intake. That can’t work on 60g glucose, because math. And if we’re maxed on 60g glucose, you’re between 48-60g fructose if you keep with their recommendation of 0.8 - 1. That puts total carb intake per their own recommendations at 108-120g, which is quite a bit less than the 144g they advocate for.

In their conclusion, they sum things up by mentioning that supplementing with fructose is good for longer endurance activities. That’s fine, and not technically always wrong. But its misleading, and it depends entirely what you’re using for the base of your sports drink. Most commonly is sucrose, which is already 1:1 glucose:fructose. To which, adding more glucose is the commonly accepted best practice, otherwise the plan would literally be, “just pour more table sugar on it” and it turns out its not quite that simple.

I’ve not seen any conclusive data that says one way or the other whether or not we can exceed 90g per hour of carb intake, given the right composition. I’ve seen compelling arguments both ways, so I don’t have a good answer on that front, excpt for try exceeding 90, and see if it works for you. But I have seen a lot of information specificlaly referring to the 2:1 glucose:fructose ratio, and until I see ANY information that refutes that, I would keep my drinks with that ratio in mind, even if you’re exceeding the standard dose by a bit.

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what you can absorb at the top level is going to be very individual. i have been experimenting with different ratios and amounts over the last 1.5mths during endurance and tempo rides on the trainer.

my personal limit seems to be around 105g/hr before i start to feel some GI discomfort. 140 seems like someone would need an absolute iron gut to tolerate and absorb that amount without GI distress being added in.

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i saw this! I tweeted them for clarification on what study shows this absorption rate. No reply yet

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please let us know if they get back to you. But i think nate has it right. eat as many carbs as you can and keep pushing the limit until you start to get Gi issue. then back it down just a bit

Was mentioned on a recent velownews podcast i think ep 83 with Asker Jeukendrup on training the gut. Can’t recommend the exact comment but Asker mentioned something along the lines of a study where subjects had successfully consumed that, but not a recommendation per se for the average joe. Worth a listen regardless and take what you will from the podcast, i found it interesting.

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Link to the podcast mentioned above. Seems items #4 & 5 will be the place of interest. (I am listening now to see if I can pinpoint the times of interest.)
- Right around 0:44:00 for at least some related info.

So, today we’ll dive into nutritional training and talk about:

  1. Applying a scientific approach to figuring out your carbohydrate needs and whether you are a fat burner or a carbohydrate burner.

  2. Second, G.I. distress. Some thoughts on what causes it and why intestinal permeability may be a factor

  3. Next, we’ll discuss race nutrition and why changing up what you eat on race day may not be your best strategy.

  4. Fourth, why most people can only absorb 60g of carbohydrates per hour but we’re still recommending trying to get 90g. That sounds like a lot, but it’s actually only about 360 calories which is still less than what you’re going to burn in an hour during a big race.

  5. The best mix of carbohydrates to improve absorption.

  6. Why you need to dedicate time every week to training your gut – no different from the time and energy you invest in training your legs.

  7. Finally, we’ll talk about any potential health concerns with focused race nutrition and briefly touch both on the microbiome and l-glutamine

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@mcneese.chad i know this is not your statement but merely a quote; but i always find it interesting when this type of claim is made, that you need to get in the same that you are burning. It fails to account for the fact that 1) we have onboard stores of glycogen, and 2) we have plentiful onboard supplies of fat that can also be used for fuel. /rant

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they are correct re: that it can’t all be absorbed if just malto or just fructose; need the two carriers, but yeah this seems like a good way of doing it

I have trained my body to tolerate 81 grams of carbs, all maltodextrin, per hour. I use Hammer Nutrition’s Heed to do so. I’ve gone from 27 grams per hour in the beginning of 2019 to 81 grams for the last month starting SSB1.

u should try adding some fructose to see if you can handle some more

How do you know how much you handle?.¨
What are the “symptoms” of not handling x carbs?

For me my stomache starts to hurt. Like bad gas or nausea

I agree. That’s what used to get me through 8-11 hours in the saddle. Took about a year of various levels of GI distress at the end of each long ride, before I’ve had it dialed down.

I’ve never actually measured how much carbs I was consuming, and all I know that it was a lot.
What I did find is that I would tolerate carbs without sugar in it a lot better when my rides were longer than 6 hours.

Thanks.

So you need to ingest allot over quite some hours to figure it out.
I remember i had some stomach pains after some long races and many gels. Not sure if it was too much carb or just too much gels which i was and still are not used to.
I only drink powder sportsdrink on training and races with maybe 1 gel at end of races that is atleast 2h.
I always do 60carb/hour because my races rarely exceed 2,5h.

just one remark on doses >100g/h. While these may be tolerated by some, there is no certainty that these doses can actually be utilized by the body. There are studies showing that you get increasing exogeneous carb oxidation when you go up to 90g/ha (or so). After that - despite having more ex carbs in the system - oxidation of these decline again. How universal such an inverted U-shaped relationship between intake and actual oxidation is, I don’t know.

All I can say is there is no way I’m downing the caloric equivalent of a whole peanut butter and jam sandwich every hour :smiley:

The gut is trainable: https://www.ncbi.nlm.nih.gov/pubmed/20466803?dopt=Abstract

Your oxidation of only glucose is at around 1g/min.
“An analysis of all studies available shows that a single CHO ingested during exercise will be oxidized at rates up to about 1 g/min, even when large amounts of CHO are ingested.”
-https://www.ncbi.nlm.nih.gov/pubmed/15212750?dopt=Abstract

You can have higher absorption of carbohydrates if you mix glucose and fructose.
“Peak exogenous carbohydrate oxidation rates were ∼55% higher (P < 0.001) in Fruc+Glu (1.26 ± 0.07 g/min) compared with Med-Glu and High-Glu (0.80 ± 0.04 and 0.83 ± 0.05 g/min, respectively). Furthermore, the average exogenous carbohydrate oxidation rates over the 60- to 120-min exercise period were higher (P < 0.001) in Fruc+Glu compared with Med-Glu and High-Glu (1.16 ± 0.06, 0.75 ± 0.04, and 0.75 ± 0.04 g/min, respectively).”
-https://www.physiology.org/doi/full/10.1152/japplphysiol.00974.2003

Upset stomach and the thought of drinking more becomes intolerable.

the author passed these three studies along but I haven’t read them yet; let me know what people see in them! @achase6002 GONZALEZ_2017_Glucose plus fructose ingestion for post-exercise recovery-Greater than the sum of its parts.pdf (1016.7 KB) O’BRIEN_2011 Fructose-maltodextrin ratio in a carbohydrate-electrolyte solution differentially affects exogenous carbohydrate oxidation rate, gut comfort and performance.pdf (443.3 KB) TRIPLETT_2010_An isocaloric glucose-fructose beverage’s effect on simulated 100-km cycling performance compared with a glucose-only beverage.pdf (254.9 KB)