Best Carbs for Cycling & Running to Keep Your Stomach Happy

A cyclist is tasting Veloforte energy bars from a table.

Getting the right balance of nutrition before, during and after exercise is a common challenge for cyclists and runners.

There are a host of factors at play — exercise intensity, ingredients, hydration, what you’ve eaten (or not eaten) beforehand…

A key fuelling issue is stomach upset — often caused by how carbohydrates are used during exercise.

We talked to Will Girling, head nutritionist at the EF-Education Easypost cycling team about fuelling. Can real, natural food help you to feel and perform better, ensuring you can train and compete in confidence, without the tummy troubles?

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The problem…

We know when your stomach is churning, you can’t enjoy your training and you won’t perform to your best either.

We know that stomach upsets, painful cramps (and even embarrassing wind) can really mess things up and anyone who has had the unpleasant experience of an event 'Portaloo' knows that digestive problems in endurance sport are pretty common!

So, if you’ve suffered the indignity of a dash behind a tree, we understand your need. We also know it doesn’t have to be this way!

“Stomach issues while competing in endurance sports, such as running and cycling, are common and problematic. But there is light at the end of the tunnel! If we understand the principles of how much and how often we can take on carbohydrate, as well as the variables that can affect tummy troubles, we can easily solve these issues.”

Why do we need carbs?

"Understanding the “why” of carbohydrates during exercise is possibly the most important pillar.

By taking on carbohydrate, one is able to maintain blood glucose and energy levels to keep performing exercise for another hour over that of a non-carbohydrate placebo.

The maintenance of blood glucose is what enables us to keep the intensity of exercise going, especially past the 90 minute point."

“So, if you’re going to be racing or out riding for longer than 90 minutes then making sure you eat on the go is incredibly important to ensure you get the most from your body.”

What are the best carbs for cycling and running?

There are many great sources of carbohydrate for running and cycling.

Natural sources of carbohydrate are easy on your stomach — because they’re real foods that you’re already used to digestion — and taste much better than artificial ingredients, as well as providing you with the vitamins and minerals you need for good health.

You don’t have to limit yourself to synthetic products and artificial sugars. On the contrary:

Bananas are always a favourite amongst sports people, and are amongst the best carbs for cycling and running with good reason. They are neatly wrapped, easy to eat and have around 25 grams of carbs, depending on their size.

The amount of carbohydrates in the form of sugar in a banana also varies depending on how ripe they are, the more yellow a banana the more of the starch has turned to sugar, making it easier to digest.

Energy bars

Veloforte energy bars provide energy in the form of two carbohydrates: fructose and glucose, both from 100% real food ingredients. This means you have quick- and slow-release energy sources in one. The combination of dried fruits, nuts and whole foods means reduced stress on your digestion.

Energy gels

While most energy gels are packed with artificial sugars, fillers and ingredients which can lead to bloating and tummy discomfort, we’ve kept our energy gels simple with dual-source natural carbohydrates and a handful of real food ingredients. They obviously taste great too.

Energy chews

Imagine an energy gel you can chew, made with real fruit juice and botanicals. A pack of 6 energy chews gives you an even greater level of control over your carbohydrate intake — up to 42g per pack — so they’re adaptable and great for combining with other energy sources for endurance exercise, or on their own for shorter bursts.

Energy drinks

We’re not talking about gross-flavoured cans of questionable fluid. It’s possible to restock our carbohydrate stores with 100% natural energy drinks — taking their carbs from natural fruit sugars. Our hydration range offers two carb containing flavours made from natural sugars, real fruit and pure electrolytes for balanced all-day energy & hydration.

When planning your carbohydrate intake, it is important to have plans not just for during, but also the night before and breakfast on race day to ensure you start with your carbohydrate stores full.

How much should I eat during exercise?

Here’s Will with the science:

“Knowing the amount of carbohydrate we can take on board during a race or per hour is incredibly valuable and could be the difference between a good race and a bad race. The amount we take on during activity is dictated by three main things:

1. Maximal absorption rates

2. Intensity of exercise

3. Duration of exercise

    1. Maximal Absorption Rates

    “This comes first as it dictates the rest. There is a fixed amount of fuel we can absorb per hour and anything over this will start to wreak havoc on your stomach. Over fuelling can be as bad for your performance as under fuelling.


    • Glucose – 1g/per min or 60g/per hour
    • Fructose – 0.5g/per min or 30g/per hour

    Glucose and fructose are both forms of carbohydrate, but they use different individual transporters to pass through the intestine wall, meaning we can combine the two and have up to 90g/ per hour."

    “Fructose is found in fruit and glucose in honey, so Veloforte bars fit in very nicely here. A single bar per hour is an ideal way to contribute towards your quota — offering around 45g of carbs per bar.”

    2. Intensity of Exercise

    “How hard you are going affects two things: when we ride hard the stored carbohydrate in our bodies (in the form of muscle glycogen) is used at a faster rate, so we require a higher intake of carbohydrate to maintain blood glucose (60-90g/per hour).

    The other side to this is that the higher our exercise intensity the less blood flows to the stomach which can cause problems with our digestion. We can improve this through training. Just like you have a training program to get better at cycling or running, you should also train your stomach to be ready for eating on race day.”

    3. Duration of Exercise

    "Duration also plays a big role with the requirement for carbohydrates. The longer we perform for, the more important carbs become.

    Exercise that lasts less than an hour (like a crit race or 10km) needs less fuel, but if you're looking at an Ironman event ranging between the elite-level at 8/9 hours and the amateur-level at around 16 hours then eating becomes massively more important.”

    How often should you load up on carbs?

    “I have researched the frequency of carbohydrate intake comparing one big feed against three smaller feeds, the results were equivocal – some participants performed better or the same with no detriment.

    However, we did see the trend of lower heart rates and rate of perceived exertion with three smaller feeds."

    For a convenient and manageable frequency to hit your target carbs per hour for cycling, running and other endurance sport, we recommend 3 smaller feedings of 20g of carbs every 20 minutes or 30g of carbs every 30 minutes, which equals 60g of carbs per hour.

    For example, that could look like:


    Other reasons for tummy troubles

    “Of course carbohydrates are not the only reason you may have tummy troubles in racing or training. Here are a few more:


    • Hydration status
    • Fibre intake
    • Dairy intake
    • Fat intake
    • Heat

    “Plan your nutrition and train with the food you will use during an event so your body is allowed time to get used to it. Follow the guidelines above on carbs for cycling and running and dedicate one session every one or two weeks specifically to fuelling as you will on race day to ensure you’re prepped and prepared.” 

    Fuel better, feel better

    Top advice from Will. By following these good nutrition guidelines every time you're out, you’ll find your stomach problems easing and your need for a panicked dash to the toilet reducing.

    At Veloforte, we believe that real food performs best.

    It's what drives us to create products that focus on three key tenets: real performance, incredible taste and 100% natural ingredients.

    Each of these is inextricably linked and together provide the optimal balance of effective, delicious and stomach-friendly nutrition that has the power to keep you going, all day.

    We know that natural foods contain a good balance of fructose and glucose, the fuels that are best for performance and best for your stomach, which is why we have based our recipes around tasty and delicious dried fruits and real foods.

    Remember, it's so much more than just eating carbs. Ensuring the optimal balance of 100% natural carbs, protein, fibre and fat mean you'll go further, better and happier.

    Tasting delicious has another important bonus. Digestion starts in your mouth, releasing digestive enzymes when you eat something you love. And the more enjoyable the food, the more likely you’ll be to stay on top of your fuelling.

    We believe the trick to keeping your digestion under control is natural, powerful and delicious food you love, eaten little and often, throughout your running and cycling, or any other endurance activity.