Should I be eating the same food and quantities for all my runs?

What to eat before a run is the most important question for all new runners. Proper fuelling is key to minimising fatigue and supporting recovery. However, your body requires different fuel sources depending on the type of training you're doing and your overall goals.


When you run, your body uses two sources of fuel (energy): fat and carbs. Fat takes longer for our bodies to break down so it’s not a practical source of energy when you’re running longer distances. Likewise, if you are running fast, you’ll need more energy in the form of carbs. This means you need to adjust your diet, based on your training demands for the day, which means it’s very likely that each day will be different.

Discover how much protein you need to build muscle as well as energy-boosting breakfast recipes and get the answer to protein and carbs – have I got the balance right? Get more tips for low-intensity and high-intensity training days.

Healthy outdoors exercising

For harder training sessions and races

Your body uses carbs, stored in the muscles as glycogen, as its main fuel source. We're only able to store a relatively small amount of glycogen, which is why eating enough carbs is important.

For low-intensity workouts

If you're jogging or walking, the body will burn fat as its main fuel for energy so eating carbs before low-intensity exercise isn’t as important.

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The most important consideration for what and how much to eat is to plan which of your sessions need to be fuelled by carbs.

How long after eating can I run?

Everyone has different levels of comfort when it comes to eating around training, so it's important to find what works best for you. In general, wait 2-4 hours before running after a large meal. This allows time for your food to fully digest. For a snack, 1-2 hours should be fine depending on how much you've eaten.

Best foods to eat before a run

Many athletes build what’s called a performance plate – this keeps energy levels high and includes equal portions of protein, carbohydrates, vegetables/fruits and healthy fats. By fuelling appropriately at meal times, a snack pre-training won’t be necessary.

As a general rule, slow-release energy foods known as low-GI are best eaten as part of your main meals (alongside moderate amounts of protein and fat), as the energy they provide is released more gradually into the blood which means they’ll sustain you for longer.

Try our low-GI breakfast, lunch and dinner recipes. For a slow-releasing snack, try one of our healthy snack options from date flapjacks to our pepper & walnut hummus with veggie dippers.

For lower-intensity or recovery sessions, you can reduce your carbohydrate intake accordingly. Restricting carbohydrate intake, called 'training low', primes the body to use fat as the main fuel during training, and promotes favourable changes within the muscle (mitochondria) that may benefit you if you are an endurance athlete. This, combined with a calorie deficit, may lead to a reduction in body fat, which is desirable for many of those planning to run a marathon.

Try one these protein-rich options:
Courgette tortilla wedges with pesto & rocket
Crab & asparagus omelette
Chicken breast with avocado salad

For low-intensity sessions under an hour, the occasional fasted session is fine, and may help the muscles become more efficient during endurance training.

Date and walnut flapjack squares

Should I eat before an early morning run and if so, what should I choose?

The first rule to train by is that you should always eat before a harder training session, as the body will require fuel from carbs. For lighter, low-intensity training, a protein-based breakfast or even a fasted training session is fine.

Here are three ways to plan:

1. The early riser

If you’re awake two hours before your run, useful fuelling options include oats, wholegrain toast with eggs, granola, bagels or breakfast muffins and freshly made smoothies.

Try these tasty suggestions:
Healthy porridge bowl
Poached eggs with smashed avocado & tomatoes
Cinnamon porridge with banana & berries
Good-for-you granola

2. Straight out of bed

If you hit the road with the minimal amount of fuss, try a small snack with quick-releasing energy, such as energy balls, fruit or a small flapjack.

If you’re really struggling to eat first thing, try increasing the carbohydrate portion of your evening meal, as this will be stored in the muscles ready for your morning run.

Recipe suggestions:
Energy bites
Easy honey flapjacks
Two-minute breakfast smoothie

3. 'Training low'

Used by professional athletes, this strategy helps the muscles adapt to endurance training. For a low-intensity endurance session, you may plan to reduce the carbs in your breakfast as this can encourage the body to burn fat for fuel.

Recipe suggestions:
Tofu scramble
Mushroom brunch
Perfect scrambled eggs

Tofu scramble with tomatoes on toast

What should I avoid eating before a run?

To provide sufficient fuel, choose foods which supply carbs, and are foods you're used to and sit comfortably in your stomach – you don’t want to experience that ‘heavy’ digestive discomfort when you’re exercising.

These foods are known triggers of digestive discomfort (diarrhoea and bowel upsets), so avoid them in the 2-4 hours before a run:

  • Foods high in fibre
  • Fatty foods
  • Spicy foods
  • Caffeine-heavy drinks
  • Alcohol
Man on a run drinking water

How long before a big race should I eat and what should I choose?

What you eat on the morning of an event should link into the overall fuelling strategy that you’ve developed and been working to during your training. Ideally, eat a meal 2-4 hours before the start of your race that includes a range of foods, depending on your taste.

Useful breakfast options include:

Can energy gels or sport drinks play a part in my fuelling strategy?

These products provide a convenient, concentrated source of carbs which makes them a useful alternative to whole foods when used by endurance athletes and for longer training sessions and events. This is because they help maintain adequate blood sugar levels and as a result maintain performance.

Most energy gels provide a fast-digesting (high-GI) source of carbs (about 20-25g) in the form of sucrose, fructose, glucose or maltodextrin. They may also contain caffeine, which may boost performance, as well as branched-chain amino acids, which may relieve the soreness associated with low to moderate muscle damage. Some products also provide electrolytes that help replace minerals lost through perspiration. However, when you're not training it's best to opt for nourishing, whole foods because of the wider nutrition they provide.

One gel provides the energy for about 45 minutes of running, but don’t be tempted to take two gels at a time because they should be spaced about 45-50 minutes apart. The secret to successful fuelling is to have the gel just before you need it. To learn when the time is right for you involves practice, so start making use of gels during your long-distance training sessions. It's important to take energy gels with water, and never on their own or with a sports drink – without water they take longer to digest and be effective. Energy gels are, in effect, a form of concentrated sports drink, so taking them with a sports drink puts you at risk of taking on too much sugar at once.

Some people prefer sports drinks over gels, these carb-electrolyte based drinks may be useful for long duration runs, however, for shorter distances and time periods they aren't necessary. Whichever strategy you adopt, be sure to trial it in training because digestive issues are highly individual.

Now you know what to eat before your run, get the rest of your training nutrition right:

What to eat during your run
How to recover after your run
How to get the energy for a workout
How to stay hydrated
Best exercises for burning fat

Are you training for an event this year? Share your tips and experiences below.

This article was reviewed on 4 December 2023 by Kerry Torrens.

James Collins is recognised as a leading performance nutritionist through his work with Olympic and professional sport. Over the last decade he has worked with Arsenal FC, the England and France national football teams and Team GB. He has a private practice in Harley Street where he sees business executives, performing artists and clients from all walks of life. He is the author of the new book The Energy Plan, which focuses on the key principles of fuelling for fitness.


All health content on is provided for general information only, and should not be treated as a substitute for the medical advice of your own doctor or any other health care professional. If you have any concerns about your general health, you should contact your local health care provider. See our website terms and conditions for more information.

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