Carb Loading - The Load Down On It 

Carb loading is the term used to describe a popular practice among marathoners that involves eating a meals high in carbohydrates, days before a big race.

The science behind it is that carbohydrates are the main macro-nutrient that fuels our energy during a long distance run.

If by “loading up” on carbs before a race, the body should have maximum stores of carbohydrates to be turned into glycogen which will be stored in the muscles and used during our runs to keep supplying us with energy and ultimately give us the ability to run far and fast. 

That was a mouthful. But essentially this is the reason behind all of those spaghetti dinners that races hold generally the night before the race.

There are people who argue about whether carb loading really helps or not.

In a half marathon it can be questionable as studies conflict on whether carbo-loading is really helpful or not. During marathons though it seems to hold fast that carbo-loading is indeed beneficial. So break out the bagels.


The Benefits of Carb Loading

  • Your body is able to store maximum glycogen (fuel used to power our running) stores in your body. Glycogen is the energy fuel source leftover after we digest our carbohydrates. This is what your body takes and burns for fuel when you run. If you do not have enough glycogen to use as fuel then you will "bonk" or "hit the wall" during your long run or marathon race.
  • Gives you a psychological edge knowing that you have carbo-loaded and have the fuel to burn.  (Even if this is the only benefit for you, this is huge in itself!)

I would definitely suggest implementing carbo-loading in your that in your pre-race week nutrition. It can definitely make a difference in your performance!


What foods are good for carbo-loading?

Pasta is one of the most common foods to eat when it comes to carb loading.

However, there are many awesome sources of carbohydrates to choose from:

  • quinoa
  • fruits - especially bananas and apples
  • vegetables - especially potatoes, corn, carrots and peas 
  • beans - although consider whether they bother your digestive system and give you gas
  • whole grains - breads
  • rice - choose brown rice
  • pasta - particularly whole wheat
  • energy drinks - this can be one of the easiest and fastest ways to get your carbohydrates in! 

I have a sample 3-Day Carbo-Loading Menu Plan here for you to use or get ideas from!

Here is also a Meal Prep Ideas for the week before a marathon to also give you some inspiration! 


Guidelines for Carb Loading

Carbo loading consists of consuming meals that are high in carbohydrates about 5-7 days before a marathon.

The ISSN states that meals should be about 70% carbohydrate in order to optimize glycogen stores in the liver and muscles.


Here are the ISSN's guidelines:

  • Start 5-7 Days before your race.
  • Deplete your glycogen stores through a long run about 6 days before a race. This can be done through a longer run and allows for glycogen muscle storage to be super-compensated as you carbo-load.
  • Consume a low carbohydrate diet for 1-4 days to allow for the super-comensation effect to occur in the following carbo-loading days.
  • Take in 400-700 grams of carbohydrates/day of carboloading 3-4 days before the race.
  • Keep running levels low to allow glycogen stores to build 3-4 days before the race.


For more information on carbo-loading + a detailed guide on the 5 day and 1 day carboloading plan & everything you need to know about marathon nutrition check out in my EAT LIKE A MARATHONER Nutrition Course!


New to Carb-Loading?

It takes some experimenting to figure out how to carbo load and you don’t want to affect your body negatively if you are not used to loading it with carbs.


So as a beginner, skip the super-compensating effect and follow these guidelines:

  • Skip depleting your glycogen stores 6 days before your race.
  • Eat a low carbohydrate meal on one day 4-5 days before the race.
  • Consume 400-700 grams of carbohydrates 3-4 days before the race.
  • Keep your running levels low.

The 1 Day Carb Loading Alternative

Some runners prefer to only do 1 day of carb-loading the day before their race and then focus heavily on there race refuel plan during the marathon itself so as to avoid hitting the wall. 

If you would prefer to do this then aim for at least 10 grams of carbohydrates for every kilogram of body weight that day before your marathon. 

Also be sure to nail that Pre-Race Meal


Want to put it altogether? 

A personal nutrition coach is pricey but you can truly be your own marathon nutrition strategist with my EAT LIKE A MARATHONER Nutrition Course!

It is the ultimate guide to eating and fueling for marathon training and race success!

It comes with a series of calculators, a 9 step plan to strategize your marathon training nutrition plan + a two step plan to be implemented the week before your marathon! It's easy to get it right with the right tools!

Don't be one of the 40% of marathoners who hit the wall! (And that doesn't even count those who drop out of marathon training altogether!)



The Ultimate Guide to eating and fueling for marathon training and racing success! + get access and develop your own personalized marathon nutrition plan to implement before your marathon with our 9 STEP Prep Plan!

Get access to the EAT LIKE A MARATHONER Nutrition Course here!

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