How To Carb-load The Right Way

It’s coming right up. Your big race. You are preparing, both mentally and physically to cross that finish line strong and proud and smiling (we’ll leave the pain that also usually accompanies a marathon out of this beautiful fantasy).

While you’ve spent the last 2 months logging the miles and building your strength and endurance, you’ll likely be spending the last few weeks fretting over all the other details. One undoubtedly being focused around food.

So lets chat pre-marathon food, shall we?

I like to say that your nutrition plan is an extension of your training plan. You put in the miles and then eat junk, you run like junk. You put in the miles, fuel for the workout and recovery properly with the right nutrients, you excel in the run, break personal records, etc. In theory, it’s simple. In practice, it can get a bit more complicated.

It’s no secret that foods rich in easy-to-digest carbohydrates, such as rice, pasta, breads, and fruits, are ideal before a run. But exactly how much, when to eat, and which to choose all suddenly become a very complex and confusing thing for runners.

The Simple Science

Once digested, carbohydrates are converted directly to glucose, which is the usable energy format for the body. There is only a certain amount of glucose (or energy) the body needs at any given time meaning that any leftover glucose gets converted into glycogen and is stored in your muscles and liver for future use. Glycogen is your body’s first energy resource and while it can also use fat for energy, the process is not efficient and requires much more work from the body.

During your long runs you first use your glucose supply and when that runs out you start dipping into your glycogen stores. It’s when you use up those stores that you “hit the wall”. The sluggish steps you’re taking, the brain fog, it’s all a result of the body now taking resources from your running effort and channeling it into converting fat to fuel. When we properly carb-load we essentially fill our glycogen stores to their maximum levels, allowing you to push longer and harder before hitting that wall, and sometimes avoiding it all together.

How To Fill Your Stores

There’s a huge misconception out there that we need to eat a HUGE pasta dinner the night before a race in order to top off those glycogen stores. The truth is that one meal alone will not fill your stores completely. Furthermore, you don’t want to be stuffing your face or overloading your digestive system the night before a race.

Your best plan is to start incorporating more carb-rich meals into your diet 2 -3 days leading up to the race. You might actually gain a kilo or two. Don’t fret. Much of this is water weight and, due to higher carb intake and less activity from tapering, is not a true reflection of your weight. In fact, this is actually a good sign that you’re carb-loading properly.

Eat muesli for breakfast, add a yoghurt and sweet potato to your midday salad and include rices, whole grain pastas and breads with your dinner.

The Right Choice 

The days before a marathon are actually not the time to be highly focused on nutrient density. While nutrient dense foods offer the body many many advantages and are critical to incorporate during your training cycle, in the days leading up to the race, we want to put as little stress as possible on our digestive system. This means starting to phase leafy greens and high fiber vegetables and fruits out of your diet, as too much fiber can cause tummy trouble midrace. Choose starchy vegetables such as peas or potatoes and bananas and more refined breads and pastas (this is your wild card to choose white rice, pasta and bread!)


Plan to eat your last big meal 48 hours before the race. Ensure it contains healthy fats (such as avocado), lean protein (such as chicken or tofu) and complex carbohydrates such as rice, potato or pasta. This will give your body ample time to digest and prevent a bloated feeling on race morning.

Twenty-four hours before the race eat normal sized meals that include all macronutrients but always contain a carbohydrate. Breakfast might be a bowl of muesli with sliced banana and 1 tablespoon nut butter plus 1 cup of orange juice for an extra carb boost. Other good choices are sweet potatoes, baked potatoes, rice and pasta.

Eighteen hours before the starting gun you should be reducing the size of your meals. Your last normal sized meal should be lunch the day before the marathon. After that, focus on eating smaller portions every 2 – 3 hours. Avoid all vegetables, fruits (except banana), high fat foods, fried foods, dairy and nuts. Focus on easily digested carbohydrates and don’t forget your fluids!

The morning of, get up and eat early! The first thing you should do is eat, so that you give yourself a good 2 hours to digest. Staying in a hotel? The easiest options are a bagel with jam or muesli with a banana.

Twenty minutes before the gun goes off take a energy gel, a swig of water and a silent reflective prayer for your body, your health, and your ability to get to where you are standing at that point.

Remember to enjoy the ride, the pain is temporary, and that gels and water are always a good idea.


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