Tag Archives: Carbohydrates

The Race Eve pasta dinner: Is pre-race carb loading a good idea?

I may or may not have touched on the folly of carb loading, that your diet and glycogen stores are a body of work, and not something you can fix in the 48 hours before your race (though your glycogen stores and physical condition are certainly something you can break in the preceding 48 hours).

Still, the Race Eve Pasta Gorge is a favorite runner ritual, and while you may not substantially improve your glycogen reserves, you at least won’t go to bed hungry.

This leads me to two questions.

  1. Can there be a situation where a Race Eve carb-load can be beneficial?
  2. Is the Race Eve carb-load beenficial for races shorter than the marathon? If so, when so, and when not so?

When is a Race Eve Carb Load beneficial?

I think there is a set of situations where a carb load might be a good idea. Whether they all funnel into one common situation or they all exist on their own, I’m not certain.

They of course depend on what your diet has been throughout the training cycle.

And of course, you are best off eating minimally processed foods. Pasta and its sauce are probably as processed as you should get. Pizza and fried food should remain out of the question until your race is over.

The key question: Have you been restricting your diet recently, whether you’ve done so throughout the training cycle or just recently?

A runner who has been cutting weight, a runner who has eaten lower-carb, or a runner who has intermittent fasted… may have a sufficient glycogen deficit that a carb load right before the race could benefit them.

Cutting Weight: Obviously, a runner cutting weight has been operating at a long term calorie deficit. Presuming training has proceeded without injury or other issues, the muscles may have spent considerable time somewhat depleted of glycogen. A big carb meal following some body-priming rudimentary activity (like a shake-out run, cross-training session, or a walk) could help maximize the available stores on race day.

Low-Carb Dieting: Few runners follow a low-carb protocol due to fast running’s extended usage of glycogen. Keto-style dieting is typically practiced by weightlifters, whose intense physical activity is typically limited to a weightlifting session maxing out around 60 minutes.

The runners who do practice low-carb diets tend to be recreational runners who either don’t run far when they do, run at a very easy pace when they do run long distance, or ultra runners who run those races at a lower, fat-burning-friendly intensity, and only eat carbs during those races, when they’re needed.

Still, provided their bodies can comfortably handle the re-introduction of carbs, low-carb dieters can also top off their glycogen stores by eating a carb-rich meal the day before.

Intermittent Fasting: Runners who practice intermittent fasting do tend to eat a lot during their limited feeding window. Depending on when they eat, it’s possible they may have sufficient glycogen stores. If they consume most carbs before or after their workouts, they’re more likely to have substantial glycogen stores. Otherwise, it may benefit them to top off their glycogen stores with a carb-rich meal the day before.

That Aside…: Barring any restricting dieting, it’s more likely that a carb-load isn’t going to provide much benefit over any other healthy meal. If you’ve been getting enough to eat throughout your training, especially following most of your workouts, you probably have enough glycogen stored whether or not you pound rotini until nauseous 15 hours before your race. The marginal utility of a carb-rich meal is minimal at best.

One notable exception: If you have been rather active in the day prior to Race Eve:

  1. First of all, you should have been resting up and minimizing activity ahead of your race. Any muscle wear/damage sustained will not fully recover before the race. Take it easy to cut your losses on any damage.
  2. A carb-rich meal eaten shortly after any activity will result in greater protein and glycogen processing and storage. Basically, what you eat will be put to greater use than if you hadn’t been active.
  3. Any muscle wear/damage from the last day will mostly remain, unfortunately. Any protein consumed (combined with sleep) will heal a bit of it, but you’ve now depleted yourself a bit ahead of the race. However, any glycogen lost will probably be restored, and possibly more.

Is a Race Eve Carb Load beneficial for races shorter than a marathon?

As long as the meal doesn’t cause a bunch of water retention, isn’t so heavy it adds weight to your body, and of course doesn’t make you feel ill… it can be beneficial to eat a carb-rich meal the night before any race between the 5K and the marathon.

Going back to the dieters… a glycogen top-off could help some runners on race day. Some extra protein could help with healing if the runner gets good sleep the night before. A Carb-Load meal would mostly help runners who have been eating low-carb or have been substantially restrictive with their diets leading up to the race.

But generally the window where this may be beneficial for sub-marathon races is even smaller than with marathoners and ultra runners. You’re not going to completely deplete your glycogen stores in anything shorter than a 20 mile race. In most race distances you won’t even come close.

This is a case where your body of work with your diet becomes paramount. If you practice a sound diet, that should be more than enough for your glycogen stores.

Rest and recovery in the days before a sub-marathon race are much more important to your performance than what nutrition you manage to successfully take in the day before. You can do more to hurt yourself from a Race Eve buffet than help.

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Using the glycogen equation

I’ve referenced this a few times. Jonathan Savage crafted an equation, out of 1993 research from Dutch professor JA Romijn, that estimates the percentage of energy you use from glycogen, vs fat, based on your effort relative to your VO2max.

y = .0021x² + .7896x – 21.031

… where X is the percentage of your VO2max and y is the percentage of caloric energy that comes from glycogen.

So, for a simple example, if I do a run at an effort equal to 70% of my VO2max:

(.0021 * 70 * 70) + (.7896 * 70) – 21.031


10.290 + 55.272 – 21.031


44.531 % from glycogen

Note: Yes, this is a massively reductionist estimate, ignoring all sorts of factors, not to mention the VO2max percentage is itself a guesstimated assumption based on what you believe is your VO2max, with your given x-percentage probably based solely on your running pace and/or heart rate. But correlative observation and evidence indicates that it’s more accurate than other methods, so here we are.

Anyway… at 70% effort, if I burn 123 calories per mile, then 54.8 of those calories will come from glycogen, with the rest coming from fat.

If (based on other quantitative assumptions) we can say I have 1208 calories of glycogen stored in my lower body, I can run about 22.0 miles at this effort before my lower body runs out of glycogen.


Now, this number probably seems low to many experts, who are used to assuming that the glycogen rate is closer to 65-70%.

At the same time, most coaches and runners are used to pushing harder on regular runs (even recovery runs) than they should. Many run their marathons harder than their bodies probably should, and it figures they burn out of glycogen before mile 20. So it would figure that most would assume a 65ish% glycogen burn rate.

Even Daniels‘ metrics flattens the slide on his similar VDOT metric, where as you drop below an 80% effort it flattens the change in the percentage of max until it assumes a rough minimum of about 80%. I would posit you can (and many do) their comfortable easy runs at far less than 80% of VO2max.

More than anything the Romijn/Savage Equation, while counterintuitive, is probably closer to an accurate estimate of glycogen use than other estimates. It’s one I go by.

Where am I going with this? Basically, this equation has some uses.

  • Let’s say you are trying to eat low carb, or at the least carb cycle to improve your insulin sensitivity and in turn how well your body utilizes ingested carbs. If you’re doing serious endurance training, you probably do need carbs. If you know your training volume and intensity, you can figure out how many carbs you can eat on a given day to fuel or offset the glycogen your body will burn that day.
  • This can help you get an idea of what pre/post workout or race nutrition you need to fuel or recover from your workout. Your protein needs should remain fairly static, and of course you need not worry too much about recovering fat since we all carry so much. But your carb needs can vary dramatically.
  • Similarly, this can help you figure out an accurate fueling plan for a marathon or longer race. By knowing exactly how much glycogen you need, relative to your estimated glycogen body storage, you now have a hard figure of carbohydrate calories you know you need to ingest. You can plan accordingly.
  • This can also help address the larger question of how many carbs you need on average. Perhaps you can set a low baseline, like 100-150g a day, and then add carbs based on how many you may burn in a typical week. The equation can give you a fairly accurate number.

There are I’m sure other examples. I’ll leave it to you to find possible ways to utilize this data.

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Training ambitions, and the unexpected prime obstacle to meeting them

Given I currently have some extra time on my hands, I’m reviewing my upcoming schedule in preparation for winter training. I want to work towards 60-70 miles a week this next training cycle, which may sound scary to the uninitiated until I mention that I was topping 50 miles per week without much trouble during Chicago Marathon training.

While I’m open to staying with a training load around 40-50 miles per week, I do want to stretch out and give 60+ a shot by extending my weekday runs, making sure I go 120-150 minutes on Saturday long runs, and mixing in some brief morning or lunchtime weekday runs in addition to my typical postwork runs. If it turns out to be too physically demanding, I can always scale back to a more regular workload, but for all sorts of reasons I’ll get into someday I believe I can now handle the larger workload.

That said, the biggest obstacle to running more miles isn’t whether my body can handle it, or even the wear on my shoes (my budget is tighter than it was a year ago, but I can always buy another 1-2 pairs of training shoes if I need it).

The problem is whether or not I can eat enough to compensate for all the extra calories I would burn.

I’m looking to get my diet super clean going into this next training cycle, as well as make it more affordable and simplified. An optimal diet that served all of the above only fed me about 2400 calories. That is well and good for weight loss, if I’m not running more than a couple miles every day. I would obviously be running much more than a couple miles per day.

Again, every mile I walk or run burns about 125 calories. I have actually been walking more the last few days, and have hit 3000 calories burned the last couple days despite no running. It’s fairly easy for me to burn calories when I’m active, and during my 30ish miles per week training days I would easily burn 3300-3500 calories.

If I’m running closer to 9 miles per day, that’s an extra 600-650 calories per day I’d burn, and even if I make the extra effort to take it easy in the rest of my life, I’ll easily burn 3500-3600 calories per day.

Okay, you may say… you’re looking to cut fat anyway, and this would be a great opportunity to shed some more of it, right? What’s the harm?

One of the reasons you don’t want to run a huge calorie deficit is the risk of muscle wasting. While it’s in general considered a cardio exercise, running requires substantial lower body strength, and along with depleting glycogen stores you break down lower body muscle. Proper nutrition allows you to rebuild those damaged muscles as well as restore your glycogen stores.

You’re already playing with fire when you run a calorie deficit, and being able to do so safely during training requires some mindful planning and execution. Even then, you should not run a deficit of greater than 500 calories a day. If I’m going to burn 3500 calories a day, I need to take in about 3000 calories to prevent myself from burning out or getting hurt.

And I probably should not take in as much fat as I have. I’m not looking to go low-fat with my diet revisions, because again the body absolutely needs dietary fat. But I do want to work on staying within 80-85g of fat per day, which means the answer to my dilemma is not as simple as committing to pounding a frozen pizza every day.

And as much as I’d like to go paleo or similar, I don’t want to compromise my performance or development by avoiding carbs and the needed glycogen.

Okay, so just eat a bunch of carbohydrates, right? Well, easy to say sure, since I’m going to burn them every day.

But there’s only so many carbs I can stomach. Most healthy carb-rich foods can be very dense and contain a lot of insoluble fiber. I found during my “sure, I’ll carb load” diet phases in previous years that the most carbs I could handle in a day is about 400-500g. And I could only hit that mark now and again: On a daily basis I can’t consistently consume more than 350g of carbohydrate.

Right now I’m eating about 300-400 calories of potatoes with dinner. I can probably handle about 3-4 bananas at most, and eating all of the above means taking in an uncomfortably large amount of insoluble fiber. Either way, I don’t think I can stomach much more than that.

Plus, your stomach can only process so many nutrients before just passing the rest or storing the difference as fat. Carbs do get stored as fat once the window closes on your body’s absorption capabilities. So eating a ton of carbs isn’t really an easy solution.


So, looking at my diet, after factoring in the foods I do and can consistently eat… I realized I had a deficit of about 600 calories if I want to train at a higher volume. How to cover it?

One answer is to swap out potatoes (at least on some days) with semolina-based pasta. I mentioned fusilli as a pasta of choice, though organic elbow macaroni is an option as well thanks to its density. Both provide more carbs in a meal (as many as 60g extra, plus some extra protein) than potatoes do overall.

However, potatoes provide a ton of potassium that pasta does not. It can be possible to supplement the traditional way: By making pasta with marinara sauce. I eat my pasta plain with salt, broth and coconut oil for seasoning. But a cup of marinara sauce adds about 800mg of potassium, which would cover most of the gap.

While it’s not totally my cup of tea, I’m not opposed to quickly heating a cup of marinara or similar pasta sauce and dumping that onto the pasta for dinner with my chicken. And, while not as much, pasta sauce also comes with a few extra carbohydrates.

I also find that sometimes at work I need an afternoon snack. If I commit to quick-prep oatmeal, that can provide some extra carbohydrate on key days.


All of these options of course have a common problem: They’re processed foods. And while inexpensive, it gets away from the whole food philosophy I’ve been working to follow and maintain with my diet. I wouldn’t want to eat these items exclusively, let alone every day.

None of this is to say I’ve found the solution. These are mostly just the options I’m considering ahead of 2019. The good news is I don’t have to find an answer now. Go-Time for this plan would be about 2.5 months down the road.

But it does present an interesting dilemma: If you want to train high-mileage, how do you make sure you get enough energy to eat to maintain that workload?

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