The Clinic

[Dogtrousers]

How does UK population correlate with TDF speeds?🤣

Spookily well.

Source: https://database.earth/population/united-kingdom/median-age

 

[M.R.M]

I've seen various studies on how much carbs people can ingest, but I haven't seen one on how this actually makes anyone any quicker. For instance, while accepting that the data is probably not all that accurate, on the Hautacam stage, if Pogacar consumed 120g of carbs an hour of a typical energy bar/gel, he'd have got his entire calories burned on the ride on the bike.

As a point of contrast, when Froome won the Giro in 2018, he was widely cited as consuming 90g of carbs an hour on the Finestre stage (where the feeding strategy was widely lauded as a factor). I haven't seen any evidence that 120g is more effective than 90g, but I'd love to see anything to the contrary.

I asked Grok for an answer with proof:

In professional cycling, is there proof that ingesting 120g of carbohydrates is more effective than 90g? Is ingesting 150g even more effective? Please provide proof.

In professional cycling, carbohydrate intake is critical for sustaining energy, delaying fatigue, and optimizing performance during endurance events. The question of whether ingesting 120g of carbohydrates per hour is more effective than 90g, and whether 150g is even more effective, has been explored in recent sports nutrition research. Below, I summarize the evidence based on available studies, focusing on effectiveness in terms of performance, carbohydrate oxidation, and gastrointestinal tolerance. 90g vs. 120g Carbohydrate Intake per Hour Evidence Supporting 120g vs. 90g:


Increased Exogenous Carbohydrate Oxidation:


Research indicates that ingesting 120g of carbohydrates per hour, using a glucose-fructose mixture (often in a 1:1 or 0.8:1 ratio), can increase exogenous carbohydrate oxidation rates compared to 90g. A 2023 study by Podlogar et al. showed that during three hours of cycling at 95% of the lactate threshold, a 120g/h intake resulted in higher total carbohydrate oxidation rates than 90g/h. However, the study noted that the additional carbohydrates did not spare endogenous glycogen stores (muscle or liver glycogen) but instead increased overall carbohydrate oxidation, potentially blunting fat oxidation. This suggests that 120g/h may provide more readily available energy for high-intensity efforts, though not necessarily through glycogen sparing.


Performance Benefits in Elite Settings:


Observational evidence from professional cycling, such as strategies used by World Tour teams like Jumbo-Visma and Ineos-Grenadiers, indicates that elite cyclists often target 90–120g/h during intense races like the Tour de France. A 2020 study by Viribay et al. on mountain marathon runners (relevant due to similar endurance demands) found that 120g/h of carbohydrate intake reduced exercise-induced muscle damage and perceived exertion compared to 90g/h and 60g/h groups. While this study was conducted in running, the findings are applicable to cycling, as gut tolerance is generally better in cycling due to less mechanical stress. The reduced muscle damage and lower perceived exertion suggest a performance advantage for 120g/h in prolonged, high-intensity efforts.


Gut Training and Tolerance:


Studies emphasize that achieving 120g/h requires significant gut training to avoid gastrointestinal (GI) distress. A 2023 article from CoachPav.com highlights that professional cyclists like Chris Froome and Geraint Thomas have optimized their nutrition to handle 120g/h, which contributes to their ability to maintain high energy output over long durations. The article cites a 2017 study by Jeukendrup in the Journal of Applied Physiology, which suggests that the body can process up to 90–120g/h with proper gut training, significantly higher than the previously recommended 60g/h. This supports the feasibility and potential effectiveness of 120g/h in trained individuals.


Study Limitations:


The Podlogar et al. study found that while 120g/h increased total carbohydrate oxidation, it did not reduce endogenous carbohydrate use, which could limit its benefits in ultra-endurance events where glycogen preservation is critical. Additionally, the study was conducted in male cyclists at submaximal intensity (95% of lactate threshold), and results may not fully apply to females or higher competitive intensities. The Viribay et al. study noted that while 120g/h was tolerated, some participants reported feelings of fullness, indicating that individual tolerance varies, and not all athletes may benefit equally.


Conclusion for 90g vs. 120g: There is evidence that 120g/h can be more effective than 90g/h in terms of providing higher carbohydrate oxidation rates and potentially reducing muscle damage and perceived exertion, particularly in prolonged, high-intensity cycling. However, the benefits depend on proper gut training to handle the higher intake without GI issues. The performance advantage is most relevant for elite cyclists in races lasting over 2.5 hours, where energy demands are exceptionally high. For most trained amateurs, 90g/h may suffice unless competing at a high intensity or in multi-day events. 150g Carbohydrate Intake per Hour Evidence for 150g/h:


There is limited direct evidence supporting the routine use of 150g/h in cycling. Some studies and anecdotal reports suggest that intakes above 120g/h (e.g., 140–150g/h) are possible with advanced gut training, but the data is sparse and less conclusive. A 2021 article from TrainerRoad mentions emerging research indicating that up to 140g/h can be absorbed using a 1:1 glucose-fructose ratio, but this is not yet standard practice and requires significant gut adaptation. The article notes that such high intakes may increase the risk of GI distress if not properly trained. A 2024 article from FuelTheRideAcademy.com references claims of professional cyclists consuming up to 140g/h, but highlights that oxidative efficiency decreases at these levels. For example, a study recorded a maximum of 108g/h of ingested carbohydrates being oxidized, meaning that at 150g/h, a significant portion may remain unabsorbed in the gut, potentially causing discomfort. No peer-reviewed studies specifically compare 150g/h to 120g/h in cycling for performance outcomes. The lack of evidence is compounded by logistical challenges, as carrying and consuming enough fuel to achieve 150g/h during a race is difficult without team support.


Limitations and Risks:


Oxidative Efficiency: At intakes above 120g/h, the proportion of carbohydrates oxidized by muscles decreases, leading to accumulation in the gut, which can cause bloating or other GI issues. Individual Variation: Tolerance for such high intakes varies widely, and most studies focus on male athletes. Female cyclists or those with smaller body sizes may face greater challenges in processing 150g/h. Practicality: Consuming 150g/h requires frequent intake (e.g., multiple gels, drinks, and chews per hour), which may be impractical during high-intensity or technical races.


Conclusion for 150g/h: There is insufficient evidence to confirm that 150g/h is more effective than 120g/h for cycling performance. While some elite cyclists may experiment with intakes approaching 140–150g/h, the marginal benefits are unclear, and the risk of GI distress increases. Current research suggests that 120g/h is near the upper limit of what most trained athletes can effectively oxidize and tolerate, making 150g/h unnecessary for most scenarios. Summary and Recommendations


90g vs. 120g: There is moderate evidence that 120g/h can enhance performance over 90g/h by increasing carbohydrate oxidation and potentially reducing muscle damage and perceived exertion, particularly in elite cyclists during long, intense races. This requires gut training over weeks to months to ensure tolerance. 150g/h: There is no robust evidence proving that 150g/h is more effective than 120g/h. The limited oxidative efficiency and increased risk of GI issues make it impractical for most cyclists, even professionals. Practical Advice: Cyclists should start with 60–90g/h and gradually increase to 120g/h during training if targeting high-intensity or long-duration events. Experimentation with carbohydrate sources (e.g., gels, drinks, chews with a 2:1 or 1:1 glucose-fructose ratio) and consistent gut training are essential. Intakes above 120g/h should be approached cautiously and only by elite athletes with team support and extensive gut training.


For further details, cyclists can refer to resources like the Journal of Applied Physiology (Jeukendrup, 2017) or consult a sports nutritionist to personalize their fueling strategy.24 𝕏 posts25 web pages4.2sHow can Grok help?

 

[phreak]

I asked Grok for an answer with proof:

Thanks for that. I suppose my question is regarding the nature of "ultra-endurance". A lot of those ultra-marathon events are 12 hours or more in length so you could very much understand why it's hard to get enough carbs in. The average Tour stage now is not really any longer in time than the average club ride on a weekend. The Hautacam stage, for instance, was under 4 hours long. It's hard to imagine a shortage of carbs is going to be an issue for a ride of that length, even if they "only" ingest 90g an hour.

 

[Ming the Merciless]

Spookily well.
View attachment 782125
Source: https://database.earth/population/united-kingdom/median-age

Is there a record of speeds across all riders in each tour? Not just the winners speeds.

 

[Dogtrousers]

Is there a record of speeds across all riders in each tour? Not just the winners speeds.

Not that I've come across.

For more recent tours you could dig out the full GC with finishing times and calculate the mean and median speed from that. But it would be a lot of work. I imagine full GC with finishing times woul become increasingly hard to find the further back you went.

I rely on the lively people/person behind bikeraceinfo to do the grunt work

 

[Aravis]

Not that I've come across.

For more recent tours you could dig out the full GC with finishing times and calculate the mean and median speed from that. But it would be a lot of work. I imagine full GC with finishing times woul become increasingly hard to find the further back you went.

I rely on the lively people/person behind bikeraceinfo to do the grunt work

In progress.

Edit: I am not bikeraceinfo.

 

[Aravis]

Spookily well.
View attachment 782125
Source: https://database.earth/population/united-kingdom/median-age

I know it was only a joke, but I'm not sure this is what was being asked for.

 

[Dogtrousers]

I know it was only a joke, but I'm not sure this is what was being asked for.

It took me a while, with some help from AI, to find a measure that had roughly those values over that timescale.

What was asked for was also a joke, so I treated the matter lightly.

 

[Aravis]

The graphs of average speed shown so far have used a false origin, which can make molehills look like mountains.

This version superimposes the overall length of each tour. So that it can appear on the same scale, and to ensure that any correlation is positive, I have deducted the distance in km from 8000 and divided by 100. I'm sure there are technical reasons why this is unsound...

Any thoughts?

Now to that other matter - I should have something today

 

[Aravis]

For the moment I've selected the Tours of 1980 and 2025 because they were extremely different:

1980: 3949km; 85 finishers; lantern rouge @ 2h 10m 52s; winning average speed 36.12 km/h.

Average speed of all riders combined 35.75 km/h (0.37 km/h, or 1.02% less than winner's average).

2025: 3299km; 160 finishers; lantern rouge @ 5h 51 40s; winning average speed 43.40 km/h.

Average speed of all riders combined 41.40 km/h (2.00 km/h, or 4.60% less than winner's average).

Only 110 to go...

 

[mjr]

I asked Grok for an answer with proof:

Well, the hallucinating Hitlerbot seems to have given a made-up citation instead of the proof you asked for, as Asker E Jeukendrup didn't publish anything in that journal in 2017. Did you bother to check before posting?

Edit to add: also, the Podlogar et al 2023 study compared glucose, galactose and mixed intakes, not intake amounts. The study used 90% and 50% Wmax exercises, not "three hours of cycling at 95% of the lactate threshold" which would be far more time-consuming to calculate and my background is medical statistics rather than biology, but is the lactate threshold for ordinary test participants constant enough over three hours cycling to do that accurately? Never mind checking it, did you even read that slop before posting?

AI chatbot use is the doping of online discussions.

 

[M.R.M]

No I didn't check. I trusted the bot to give accurate results, just as I would a Google search. Sorry if it's incorrect.

 

[mjr]

No I didn't check. I trusted the bot to give accurate results, just as I would a Google search. Sorry if it's incorrect.

OK, thanks. At least now you know: first-hand sources tend to be more accurate than Wikipedia which is more accurate than Google search results these days which is more accurate than Musk's Hitlerbot and its ilk. The Daily Mail is somewhere between the last two.

 

[Dogtrousers]

AI chatbot use is the doping of online discussions.

Except doping actually works

 

[M.R.M]

Well, the hallucinating Hitlerbot seems to have given a made-up citation instead of the proof you asked for, as Asker E Jeukendrup didn't publish anything in that journal in 2017. Did you bother to check before posting?

Edit to add: also, the Podlogar et al 2023 study compared glucose, galactose and mixed intakes, not intake amounts. The study used 90% and 50% Wmax exercises, not "three hours of cycling at 95% of the lactate threshold" which would be far more time-consuming to calculate and my background is medical statistics rather than biology, but is the lactate threshold for ordinary test participants constant enough over three hours cycling to do that accurately? Never mind checking it, did you even read that slop before posting?

AI chatbot use is the doping of online discussions.

Based off this article linked by Grok in my question, the original question of phreak on whether 120g are more helpful than 90g on the bike, is very much answered positively. Anecdotally, Matteo Jorgenson also states that he consumes more than 150g per hour and that it has helped him in his performance. The latest Unbound winner also mentioned more than 120g per hour in his win and so has Cameron Wurf during his Iron Man races. So, I'd hardly consider the post "slop". The post (by Grok) also gives an alternative viewpoint stating that 120g can be better than 90g, but doesn't necessarily mean it has to be.
While we're at it and asking questions, is this level of politeness the best you can muster? I'm sure you're capable of posting in a less nasty manner considering you were not provoked in any way. This level of unfriendliness just makes you come off as a complete c*nt to me. Maybe you're used to be seen that way.
You also seem to presume, that just because I linked a summery to answer phreak, that I have the obligation to read each and every study cited or link posted. While that may be the case in the fantasy land in your head, I have no such obligation. I was trying to be helpful regarding phreak's question. The person asking the question can read the additional documentation to the level of his or her interest. While the goal shouldn't be to post misinformation, the original question was actually answered in my post. The subject is of moderate interest to me, so I am certainly not going to read every single study on the topic in entirety. If you are more of an expert you are more than welcome to chime in, but you didn't, did you?

Your love or hate of Elon Musk and his activities and companies are of no concern of mine. He is a rather divisive person and I'm sure plenty of people have plenty of opinions about him. I'm hardly a fanboy. I don't see however, why your distaste for him needs rub off on me in terms of your verbiage. As mentioned above I don't appreciate it at all (while still acknowledging that it's my mistake to post incorrect information if the entire answer from Grok wasn't entirely accurate). I'd rather be more friendly in my favourite cycling forum.

Edit: Also the Podlegar study referenced seems to be this one:

1. Podlogar T, Bokal Š, Cirnski S, Wallis GA. Increased exogenous but unaltered endogenous carbohydrate oxidation with combined fructose-maltodextrin ingested at 120 g h−1 versus 90 g h−1 at different ratios. Eur J Appl Physiol 122: 2393–2401, 2022. doi: 10.1007/s00421-022-05019-w

And not the one "Postexercise muscle glycogen synthesis with glucose, galactose, and combined galactose-glucose ingestion" you linked.

Edit2: Regarding Jeukendrup, I found this publication from 2017 which is probably what Grok is referencing. I am unable to find the citation you are referencing in the Grok post regarding Jeukendrup not having published anything in a specic Journal in 2017.
I certainly hope you weren't talking about this, "For further details, cyclists can refer to resources like the Journal of Applied Physiology (Jeukendrup, 2017) or consult a sports nutritionist to personalize their fueling strategy." As that would be rather stupid to base off your level of criticism, since that line doesn't even reference a specific study.

So, honestly I don't know what you have actually contributed to the actual question, besides make me waste time, due to getting all riled up by your condescension.