High Carb intake a risk for diabetes?

there is a view in sports science which thinks “i’m an athlete, i can metabolise anything”, ie. athletes are somehow immune from the consequences of a bad diet (high g.i. foods). this is false. exercise reduces the spike in blood sugar levels, but doesn’t negate it.

if you’re concerned:

  1. get a blood test for glycated haemoglobin (HbA1c)

2.get one of those diabetes apps which details the g.i. value of foods and, more importantly, the g.i. loading of foods.

3.consult a cardiologist who specialises in atherosclerosis.

the advice of the trainer road ‘team’ on this subj. is not helpful. they buy and consume maltodextrin as a matter of daily training (an incredibly stupid thing to do). their concern is purely with performance (ie. ingesting sufficient quickly-absorbed carbohydrate). the health consequences are not considered.

save the gels and ernergy drinks for races or very long rides. try to use real food whenever you can. there are low g.i. refined sugars available you can add to your electrolyte mix for carbohydrate energy requirements.


This is perhaps too hot a take. I totally understand where you are coming from but I think it is a bit to black and white. For me, you are right and I only use it for really long stuff. For the podcast team, and many who may read this daily malto is probably fine.

A metabolically healthy individual eating within shouting distance of energy balance can certainly consume malto without any danger. If you have no family history of T2, have little body fat like the presenters (and thus probably dont have much fat in your liver either, but its possible. Its more common in some Asian populations to have one without the other) , train some 2 digit number of hours per week (and thus probably have non liver locations to store the glucose) and get the vast majority of your calories from healthy whole foods (so you likely have some metabolic flexibility) it is probably not a big deal if you eat 85 calories per hour in glucose.

I have trash genes, belly fat, only 6-8 hours per week of training and 40 previous years of crappy diet as baggage but I am looking at the numbers from live CGM data that show me I can have pure sugar during any effort above a slow walk and not get an unhealthy insulin spike.

for those wondering:

refined sugar (70)
maltodextrin (100+)

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I cringe every time those skinny dudes give diet and weight loss advice. They just have no clue what it’s like to be over 50 and not be able to lose that last 15 pounds no matter what you do!


Responding specifically to the OP, I’m not aware of any long term study offering any such assurance that there will not be long term consequences for athletes consuming such large quantities of simple carbs such as maltodextrin, fructose, cluster dextrin, “super starch”, or dextrose. The bottom line is that we do not know with any certainty one way or the other at this point in time. There are clearly varying opinions on the matter. Generally speaking, the old saying “everything in moderation” has always been a sound principle to rely on when it comes to long term health related issues. Getting as many of our calories from real whole foods and then supplementing with calories from simple carbs when whole foods are not available or feasible is probably a good strategy. Cheers.

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the book “Peak” addresses this subject in depth. It’s a compilation of recent studies dealing w/ high level performance outcomes. The author has a running theme of “fitness/performance” versus “being healthy”.

This again is my point: that the carbo intake advice may need to be stratified according to age ( as a broad category)

Don’t blame the fuel.

Or contact Tim Podlogar.

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I do have an issue with pushing the high carb food in general. While I completely agree that in exercise you have to fuel, and sugars are the best way to get fuel in, I have a major issue with encouraging the high carb food outside of exercise.
In that Fast Talk podcast, they ended up talking about nutrient density as a much better metric than pure high/low anything (carb or fat).
I know what works for my body, and it is not high carb, even on the bike I am not consuming huge volumes of sugar, but I do use as it is the easiest to keep food coming in. Distilling this to a sound bite for a podcast is crazy, and I cringe at the older trainerroad podcasts talking of how much low nutrient food was being consumed off the bike to hit some mythical number.

I’m pretty sure they absolutely push a high nutrient/natural/organic diet off the bike. And only advise carb fuelling during workouts.

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Chad mentioned this on one of the podcasts last year, but after watching hours of the TR podcasts I can’t for the life of me find it. I’ve searched elsewhere to no avail. Does anyone know if there is a name for this (what seems to be distinct) form of metabolism?

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From about 12 minutes

As an avid podcast listener already, I did indulge you to refresh my memory…that’s race specific, not just every day training, and its 3 years ago. Nate’s really cleaned up his nutrition since too.

I dont know where it is in the podcast but the relevant terms are “GLUT1 transporter” and “non-insulin-mediated glucose transport.” The GLUT4 transporter is the “normal” insulin controlled one. Prepare yourself for a rabbit hole, but an interesting one. The peter attia podcasts on the topic is a good gateway drug to the papers themselves.

@Bob_Builder I had to adjust all of this since my last Dr. Visit and blood draw. It is definitely individual. I ended up with high triglycerides etc…blah…I have since reduced my sugar intake in all parts of my life, but do not try for 80-100gr per hour on the bike. I eat what works with real food and some smaller carb dosage from Scratch (27g over SIS 36g). Plus use UCAN with great success. I can get the calories I need with the carbs I need when I plan on the lower side and can maintain some good pacing over 2-5 hours. I am much happier and when I see the Dr in October for another draw I am hoping to be far better for it. It’s our health that we need to take care of rather than winning masters races. I just finished a local hilly TT and did well Mercx style, at 21.9 mph average over 17.4 miles. 10th of 17 everyone (1-9 )on TT setups that would make Pogocar jealous… were half my age but I also blew away the young ones as well 11-17 places. Better to fuel with what works and stay up on blood work and nutrition ON and OFF the bike. I am 51, 5 11, and my ftp is rather low 268. Fast because I want to be. :-). I do wish the coaches would re-asses this mess on the podcast. But pretty sure that will not happen. I am also starting to meet with a nutritionist…I am riding a big European Sportive in 2022 and need to dial everything in. Be sure to read the responses witch caution, including mine. Some here think they are helpful, while not, boasting about their situation. It is individual.


Good question and thought line. I wondered similarly. Turns out, when you slam sugar during training, you don’t get massive insulin spikes. Hardly any at all, actually. Epinephrine is released in training. Epinephrine blunts any upregulation of insulin production by the pancreas.

The muscles still uptake glucose because they become a couple orders of magnitude more sensitive to presence of insulin during exercise.

TLDR: you’re good to go.

Get your a1c checked every couple years and pay attention if it starts moving over 5.4. 4.8-5.4 is probably optimal. Depends on who you ask. If a1c is good, you don’t have any inflammatory issues that are being caused by sugar.


I’ve been lurking in this thread for a while, but wanted to chime in a bit here with a bit of perspective.

Carb intake can and should be matched for not just racing, but also training, in the context of workload.

If you have a 200w FTP, and are doing endurance work around 130-150w, you are burning roughly 450-500kj per hour, at a reasonable fat percentage and you don’t need to necessarily be putting down 60g of carbs per hour unless the ride is going to be long.

In my case, when I’m doing long endurance work around 230-270w or a long sweetspot workout, I’m burning between 800-1000kj per hour. 60g per hour is the minimum I need to take in in order to not end up in an absolutely massive energy deficit.

I’ve listened to the podcast for many years and I’m not sure where folks are getting this misconception that the hosts are advocating for consuming lots of simple carbs outside of the context of training.

Several people have also mentioned the fact that during exercise and in a relatively wide window afterwards, your muscles are able to uptake massive amount of glucose without much or any insulin at all.


I guess it depends on what you mean by “outside the context of training.” We’re all “athletes” here, so average-joe-on-the-couch is a whole other context. Would you say eating a box of cereal because you had a workout this morning (or a workout tomorrow) is in or out? I would say it’s out while fueling the ride you currently doing and/or just finished is in. While the podcast pretty frequently touches on consuming carbs during a ride, they just as often are telling you to eat as many carbs as possible the rest of the day to recover-from or prepare-for a ride – ie, all the time.


That seems to be more Nate but, of course, he’s a tall skinny guy. Jonathan seems to be more in the middle. And Chad said recently that he tends to be more of a protein/fat eater naturally.

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Good ear, I was definitely channeling Nate for the box of cereal :rofl: I considered adding an offhand remark to my post but thought it would detract too much.