Should you eat before a run?

Knowing what to eat and when before doing any exercise can send even the most experienced triathlete into a spin. But before going for a run, the nutrition guidelines really are quite simple…

Is it safe to eat before a run?

Yes! In fact it should be encouraged, not only to fuel your run but also to help maintain a healthy hormone balance. If you are heading out first thing and you haven’t eaten since dinner the night before, it’s important that you have something before your run, even if it’s a small snack.

Fasted training can lead to a spike in cortisol, which, if frequent overtime, can lead to a negative impact on performance and health. Women should be aware these can include disruption or cessation of the menstrual cycle.

• Are you more prone to injuries if you run early in the morning?

What are the benefits of eating before a run?

By eating a meal or snack before a run you can improve your carbohydrate availability and prevent your body from tapping into its glycogen stores straight away.

Meaning you can run further and/or at a higher intensity and reduce recovery time, due to being less likely to completely deplete your body of carbohydrate.

What foods are best eaten before a run?

It’s one of the most popular questions in running, and one with multi-faceted answers. If you’re planning a long run or a session that’s packed with intervals, ideally you’d look at what you eat in the preceding 24hrs, if not day-and-a-half.

That’s because you’ll maximise the session by packing your glycogen stores. These are predominantly in your muscles and liver, and are how you store carbohydrates.

You want to focus on good-quality carbohydrates, so your preceding day’s meal breakdown could look like: breakfast – a round or two of toast loaded with peanut butter and a banana; lunch – jacket potato with tuna and a salad: mid-afternoon snack – a slice or two of Maltloaf; evening meal – chicken stir-fry with rice followed by a dessert of Greek yoghurt and fruit; supper – rice cakes with a topping of your choice.

What should you eat before the following day’s run?

As a general guideline, it’s recommended that you wait 3-4hrs after a large meal before running. If you’ve had a small meal or snack, wait a minimum of 30mins or preferably 1-2hrs before going for a run.

Obviously, if you’re running in the morning, a 3-4hr wait’s unlikely. So, go for something carbohydrate-heavy but not too large. Good options include toast, Scotch pancakes with a banana on-board and bagels coated in jam.

More scientifically, if you’re running for an hour or less, aim to eat around 1-1.2g carbohydrate per kilogramme of bodyweight. A round of toast contains around 58g carbohydrate, so it’d be one round plus maybe jam for a 58kg runner.

You could aim for a similar amount if you’re running longer than an hour – maybe a little more – but fuel during your run with gels, drinks or chews. Aim for two gels an hour. You don’t really need to fuel during a run under 60mins.

If you’re short of time in the morning, you could knock back a sports drink. Ideally sip it rather than down in one as you’ll retain more of the carbohydrates.

You should also knock back an espresso or two, as there’s a substantial amount of evidence showing that caffeine can help endurance performance. How is by reducing your perception of effort and pain.

To enjoy the benefits of caffeine, the standard recommended dosage is between 3 and 6mg multiplied the runner’s bodyweight. It would translate into 210 to 420mg for an individual weighting about 70kg.

If you go below that, the benefits will still be there, but to a smaller degree. Above that and you increase the risk of undesirable effects such as jitters, anxiety, agitation etc, and of course, these may make your performance worse instead of helping.

Are there any drawbacks to eating before a run?

With correct timing and fuel choice you’re only going to benefit from fuelling your run. If you eat the wrong food, too much food or don’t leave enough time for digestion you could end up with some gastric discomfort.

As mentioned, experiment with your fuel and timing to find what works and doesn’t work for you.

• How does endurance sport affect your digestive system?

Does what you eat depend on the length of the run?

Yes, for longer runs you might want to increase the portion size and the gap between eating and running. For your long runs, a meal or substantial snack with complex carbohydrates will provide a more stable and prolonged release of energy, reducing the risk of ‘hitting the wall’, AKA running out of carbohydrate.

You might also need to fuel during your run. For shorter or faster runs you want to consume quick release carbs closer to training – sweets, jells or fruit juice all work well.

Fuel your training and reap the benefits in your races!

• Triathlon nutrition – our ultimate guide to fuelling