Fueling Workouts

That’s okay.

I never made the point that one shouldn’t fuel their workouts.

My questions was about what’s wrong with saying “earn those carbs” in the context of an super easy workout. Especially because fueling isn’t needed for those rides.

So, a person could look at the work as a way of working towards a treat. Especially as most of us do this sport as a hobby and not for a living.

On the other hand, slightly different stories are also in Matt Fitzgerald’s book “the endurance diet” where some pros talk about how they combine the work and sweet tooth aspect to make the best out of both worlds.

You’re right.

Needed ≠ Optimal.

It may actually be quite reasonable. Especially in the context of seeking either of the following:

  1. Maximizing performance at threshold workouts or above. Reason: chronic presence of high glycogen content tends to promote the creation of glycolytic cellular machinery. Essentially you get better at burning carbs at a higher rate, which supports higher work rates (power outputs).
  2. Improving body composition. Nighttime overeating, especially on high-fat, or calorie dense foods, tends to be strongly promoted by earlier hypoglycemia. Hypoglycemia is a common result, even if mild, of training without intra-workout fuel.

You are absolutely right though, that excess worry about carb consumption for quite easy workouts is very misplaced. But it’s probably worth at least some thought.


Yes, but, exceeding burned carbohydrate with consumption is actually a great idea. 2 reasons:

  1. Increased blood glucose during training results in reduced RPE and less fatigue from identical lower-intensity stimuli, with potentially enhanced adaptations due to higher glycogen content post-ride.
  2. z1 and z2 rides are great opportunities to stockpile glycogen with higher-carb feedings so that future trainings sessions can be of the highest quality and with the lowest fatigue at onset of training.

Sounds like a great idea.

This may actually be still too low for the hardest of 4-5hr ride days. My wife routinely consumes 10g/kg ON THE BIKE during a 5-hr ride. (600g carbs, 5 hrs). She also eats another 250-400g carbs off the bike on a day like that, quite easily. (13-15g/kg/day is quite common). She might average 180-200W for such a ride, at 63kg.

This might help: Table of Intra-workout Carb Needs Per Hour of Training

I have coached several hundred clients in endurance sport nutrition. Never once have I thought to myself: “oh that’s over-fueling.” The only sign of over-fueling is gut distress, unless we’re talking about someone who is literally capable of consuming more during their ride/run than they’re capable of burning. Very hard to do for anything but a glass cranks ride.

@TwoWheels I think your approach laid out here is great.

Your weight gain may have been intra-muscular carb weight + water + gut contents. Could have also been fat tissue if you consumed off-the-bike as you typically had been doing without proper intra-workout fueling. Probably a bit of both. I’d recommend continuing your higher-carb fueling strategy and just reducing off-the-bike kcal slightly if weight drifts up. Performance will be better without a doubt.


Thanks for your comment. You wrapped it up better than I initially did. Especially the paragraph I quoted above. Perhaps another try: fueling workouts is important and it becomes more and more important the higher the intensity gets and/or the longer the workout becomes.


Thank you for your extended reply. It is certainly my hope that this thread is helpful to others who may have a similar question or wish to take a similar approach.

Just to update where I am, I a haven’t lost ay more weight but have stayed with in a pound of my starting weight, certainly nothing to worry about. I lost a pound per week the first 2 weeks, but I think I may have been under eating. Now that Ive just finished week 4 or SSB II MV my appetite has increased and Im trying to focus on eating to appetite. Also, my RPE on the workouts has also increased. Granted the IF does progress week to week in the plan, but I wonder if I was under eating a bit.

Anyway, I’m going to keep carbing and keep eating, probably eating slightly more. Im trying to remind myself to only make small changes, no huge changes or swings. Hopefully FTP test in about 2 weeks will show some positive results. My goal is to get to 4 w/kg this year.

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I agree with this. I get this message on Phoenix and the advice doesn’t seem to line up with the more recent position on fueling. I think maybe even the whole nutrition text segment on Phoenix may need revisited

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I have another question for fueling workouts.

Let’s say i consume 100 gr carb per hour and i did 2 hours interval (4x20 mins %90) and I burnt 1700 cals (320w ftp). And i consumed 200 gr carb which makes 800 cals (but i burnt 1700).

So my question is that i consumed 100 gr carb per hour and did i fuel my workout well?

P.s: i wonder because i also want to make deficit (want to loose weight). By just consuming 80-120 gr carb per hour means fueling well? Or what?

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The short answer is:
Yes you fueled well. Create the calorie deficit outside of training by consuming in moderation farther from training times. Generally using a moderately-high protein, high-carb, high-volume-food, lower-fat dietary approach seems to both facilitate fat and weight loss, as well as sustain and enhance performance.

I wrote a book and calculator to help with exactly that, quantitatively, FYI.

I make money off them. Full disclosure.

The The RP Diet for Endurance (ebook) has been added to the Trainer Road Official Recommended Books / Reading Thread, so I suppose it’s okay to share here.

They’ll solve everything for you. Very step by step. I don’t really know where the boundary is here on TR for that sort of discussion so I’m just going to copy-paste a private response I wrote, which was well-received by another user who was already familiar with the company through which I sell the book and calc spreadsheet. (“RP”)

"Awesome. Yeah the RP Endurance Macro Calculator (EMC) is the best option for sure, if you have to pick between the RP App and the Calculator.

"The app has amazingly useful features and is beloved by many, though.

"It can absolutely be used alongside the RP Endurance Macro Calculator (EMC) , or the EMC can be used as a standalone.

"In very brief, with a bit of situational vagueness with regard to the quantitative side of things, here are my steps for dialing in diet as an endurance athlete:

  1. Figure out total macros for the day. (use RP Endurance Macro Calculator (EMC) or similar calculations)
  2. Define intra-workout carb needs. Use Table of Intra-workout Carb Needs Per Hour of Training
  3. Caveat: Add more workout carbs if no solid meal pre-training. Usually 20-70g carbs, added to intra-workout needs, as a pre-workout booster depending on the duration of the first session.
  4. Calculate remainder of carbs for the day, which will be “healthy carbs.” (just not junk, but sometimes sweet stuff is great too).
  5. Split relatively evenly about 60-80% of those healthy carbs pre- and post-workout. Allocate more heavily to “inter-workout” meals (between workouts), especially if there is only one meal between 2 workouts.
  6. Taper the rest of the carbs away from the training times.

"Protein allocation goal: spread throughout the day, and don’t interfere with training digestion.

"Fat allocation goal: spread throughout the day, but not inter-training or during training ever. Slows digestion.

"Veggie allocation goal: spread throughout the day, but occasionally not inter-training if I think digestion rates may be substantially slowed.

"The app is AMAZING for optimizing and streamlining if all you do is lift, or short-endurance stuff only, or just generally want body composition change. It’s much less optimal for endurance workout fueling and meeting macronutrient needs of endurance athletes. The best of both worlds is to use both the app + EMC, for sure. If picking one thing: EMC is your go-to.

"If your endurance activity ALL falls under ~75min per session, AND you train less than about 8 hr per week, then the app alone will work quite well.

“If you don’t need/desire the app for the meal-by-meal optimization, tracking, logistics side of things, then the EMC can be used very well as laid out above.”


Jumping on the workout fueling bandwagon, I’ve been ingesting homemade recovery drinks for the last month+ following hard workouts on the MV plan (2:1:1 maltodextrin/ fructose/ whey protein). I’ve also been kickstarting 5am workouts with a few gulps of maple syrup along with a big cup of black coffee.

The good news: I feel very good both on the bike & in post ride recovery. Somewhat concerning is my recent blood work glucose level nudged into “pre-diabetic” territory. A follow up test retreated my number just shy of the danger zone.

Looking back at a handful of blood work results over the past decade my number is as high as its ever been and about 10% above my previous average.

Surprisingly I have heard nothing about blood glucose levels in conjunction with carb workout fueling. It sounds like a logical but negative side effect that would warrant attention

Anyone have similar experiences?

If there has been weight gain alongside the increased workout fueling, this is an expected (and not ideal) outcome. Calorie reduction elsewhere is advisable. Consider not exceeding these amounts. Table of Intra-workout Carb Needs Per Hour of Training

I have experience working with hundreds of athletes newly implementing very high sugar fueling strategies, and have found zero who were moved into prediabetes independently by using high-carb intra-workout fueling.

Exceptions include:

  1. Weight gain.
  2. Very low training volume.
  3. Protein consumption below 0.4g per pound of body weight per day.

TBH… I’ve only seen it happen in scenario 3, above, but could see it happening in scenarios 1 & 2.

FYI: It’s not at all necessary to maximize rate of glycogen storage by way of malto+fruc post-exercise if you’re training once per day. I would not use a mix like that any time other than during training. Probably much more healthy and satiating, and at least minimally less likely to cause sugar regulation issues if you stick with more nutritious carb sources than malto+fruc post-training.

I’m on a deficit the last few months and lost 4 pounds. During this period i fueled all of my work (Endurance rides and Treshold or above ) with 75G of carbs per hour and it felt amazing! (SSB MV+)
Loosing weight AND gaining strength is a fine balance. But fueling the work is very important.


Hi, is this specific to that question (high blood glucose) or a more general recommendation?

If the latter, I thought one of the primary purposes of a post wko recovery shake (CHO + PRO (of whatever ratio … that’s another pit of confusion for me on this topic!) was the speed at which you can recover the calorie deficit from the wko and start the signalling / recovery process?

  • eg: “The current research suggests that consuming between 1.0 – 1.2g of carbohydrates/ kg of total body weight/ hour is optimal for muscle glycogen replenishment in a short window of recovery.” * [ref: TR blog]

Or do you include a recovery shake during cool down / immediately after as still being “during training”?

eg 1200 cal wko:

  • 800 cal ingested (drink & gels) during the intervals
  • 400 cal ingested (with 20g PRO) in recovery shake during cool down / immediately after


Mostly general, but also very specific to the elevated blood glucose concern.

That is the purpose… but it’s actually not that necessary for one-a-day training, especially if you’re fueling well during training. And I’m about as pro-sugar pro-carb pro-glycogen replenishment as a person can get!


This will work nicely for glycogen repletion. It will not be the most satiating and probably not quite as healthy long-term as choosing more fibrous and nutritious carb sources. It’s not necessary to absolutely maximize glycogen storage rates post-workout unless you have another workout happening very soon, or unless there was substantial depletion (ie. a long fairly hard ride). Total magnitude of glycogen storage can be maximized over the course of the day, without maximizing initial glycogen repletion rate.

I personally do a bit of a mix of sugar (or malto+fruc, if you don’t like the idea of sucrose), alongside fruit, milk and whey, or any other protein… mostly because I like the taste and like to drink things other than sugar syrup… which I promote during training for sure!

Nutrient timing and digestion/absorption rates matter to a much lesser extent when training is only one-a-day. Making the post-workout shake purely an optimal blend for maximizing glycogen resynthesis isn’t necessary and the tradeoffs are:

  1. More kcal coming from fluid sources = lower satiety.
  2. More sugar consumption, perhaps in excess of glycogen depletion. May or may not be problematic.
  3. Lack of fiber and micronutrients (health focus) from a greater % of kcal for the day.

I’m all for:

  1. Absolutely maximizing / optimizing carbs/sugar intake during training.
  2. Maximizing glycogen repletion rates post-training when the next training bout is same-day and requires high glycogen.
  3. Maximizing glycogen repletion rates post-training when a person has ZERO issues with weight and is at optimal body composition, and has perfect blood sugar regulation, and no issues with satiety, ever.

Otherwise: I’d just generally target “high enough” glycogen repletion rates and rest assured that adequate daily carb intake 'round the clock will satisfy the rest. It will.


Thank you, that has made the subject a lot clearer to me. The explanation is much appreciated.

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Hello everyone,

I have a question about fueling.

I am only using maltodextrin for fueling but as far as i understood i can use it about 50-60 gr for an hour. So i want to increase that number but i confused a little bit. My question is about dextrose. If i buy dextrose and combine it with maltodextrin, will it be good solution for fueling?

I dont know about types of carb and thats why i wonder malto and dextrose are different carbs right? So combing them will be better for fueling?

I am 76kgs with 1.88 cm heights so i am kind of big rider and i guess 50-60 gr carb is low for me so i wanted to ask this question.

This should be pinned for all forum users!


I just want to mention that since I’ve started fueling EVERYTHING I’ve felt so much better throughout the day. Just last night I managed to take on 120g of carbs during Pettit. Next time I’m going to try 130g. I seem to have a freakish ability to consume carbs without GI distress so I’m going to see just how far I can take it and find the limits of this pretty big genetic advantage I seem to have.


No. Unfortunately that won’t work.

Maltodextrin is just strung-together dextrose. Thus, both dextrose and maltodextrin contribute to the saturation of your gut’s glucose transporter channels.

Pair maltodextrin with fructose instead.

Or use less maltodextrin and some sucrose. Sucrose is a disaccharide (2 sugar units combined) of 1 glucose and 1 fructose, FYI.

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Probably has been address here at some point…

but regardless…

Let say I have a WO that will burn around 800C…

Should I load the calories BEFORE the wo (say consume about 600 c) or split between pre workout and during the wo (say eat 300c and then consume 300 during the wo).

Thanks in advance!

C / c = kcal?
C / c = carbs?

I’m assuming you’re using C & c interchangeably to mean kcal right?

If so, then 800kcal ride probably means you should be eating somewhere between 200-350g of carbs over the course of the day, depending on goals, activity level, etc.

Regardless, answer depends on duration of workout.

If you burn 800kcal over the course of a 2-hr ride, you’d be better off having a higher percentage of your day’s carbs intra-workout, than if you were to burn 800kcal in under an hour. Could have a very light breakfast and do most of the fueling intra-ride.

If you’re hammering the power and workout duration is shorter, it makes more sense to put a good chunk of your carbs pre-workout and post-workout, and not bother targeting anywhere near the upper tolerable limits of carb consumption during training.

Exercise duration is a primary driver for carb consumption rates.