Updated: September 22nd, 2021
Proven nutritional facts to fuel your long runs: pre, during and post run.

I get it.

Knowing what to eat before a run is tricky; especially if you’re an early bird runner, or running to lose weight. On the one hand you want to be minimising the calories to create a deficit, but on the other hand, if you don’t fuel your run, you’ll inevitably underperform.

The misconceptions around nutrition are so vast from the latest dieting digests to avoidance of soya-based products and how much protein is too much. It can be hard to sift through the noise for actual evidence-based nutritional advice. Who’s advice do should you listen to anyway?

Without being a nutritionist, you know a poorly balanced diet leads runners into a pitfall of fatigue. Insufficient fuelling for your training runs impacts not only our training session but you’re tired all the time. Irritable with a much much shorter fuse. Lacking concentration impacting your work, and even safety whilst driving. Leading to bone density issues, menstrual cycle disturbance (or absence altogether).

To oppose such side effects, you must incorporate high-energy foods into your daily meal plans– I mean, who wants to run out of steam? (Pun intended). Especially if you’re on a training plan and need to keep up with ever-increasing training demands. There is no one-size-fits-all approach to running nutrition, general guidelines given strong parameters for you to play with, and find what works for you.

Man resting in the road

How to fuel before a run

As a general rule, eating 60 mins before you head out of the door gives enough time for the food to digest but also provide the boost of energy just when you’ll be needing it. (Although if it’s high 8/10 intensity, then opt for an additional carb-fuelled bite to eat 30 min before running).

Ideally, this snack is high in carbohydrates (foods such as fruit, whole grains, vegetables and dairy). The portion size, time of the day, and the snack itself will differ from runner to runner so find what works for you (I rely on peanut butter on a wholemeal bagel or a banana to see me through). Although if you’re attempting to lose weight with running, you may be somewhat wary of bread but wholemeal toast is seriously hard to beat. Carrying around 56g carbs which should be enough to keep you going.

For a more comprehensive view of it, ultra-x running events recommend:

  • Low intensity/rest days: 3 grams carbs per KG of Body Weight (BW) /day.
  • 1 hour moderate training a day: 5-7 grams carbs per KG of BW /day.
  • 1-3 hours training a day: 6-10 grams carbs per KG of BW /day.
  • 4-6 hours training a day: 8-12 grams carbs per KG of BW /day.

For example a 70 kg man would require 420-700 grams of carbs per day for 1-3 hours of training. Now you could split this directly into 140- 233g of carbs per meal (for 3 equal meals a day) although, don’t forget to consider the carb intake throughout your run also?

You see, If the run exceeds 90 minutes, then we need to be snacking on some form of carbohydrates during running too, to ensure there is enough energy available to use.

Jar of carbs

How to fuel on the run

The stored form of sugar (glucose) is called glycogen, kept in the muscles and liver ready to be used as energy. It is the preferred method of energy sourcing as it is quicker to absorb, but arguably, fat has its place. Fat is also an energy source and there is an ongoing debate if fat can sustain you better than glycogen for longer distances.

The glycogen we have in store will run our before the end of a marathon (especially for a quicker runner) it’s believed that the energy store we have ready to go is used during the first 10-15 minutes of exercise then is complemented by the pre-run snack for fuelling from there.

Runner eating

So on longer runs we need to keep energy (glycogen stores) topped up, once you feel your energy levels starting to dip; it is too late to maximise the benefits from calorie intake. Here’s how to stay ahead of the game:

  • Easy/recovery runs – fuel pre-run but its unlikely to warrant extra fuelling during the run, especially if its under 60 minutes.
  • Speed/tempo runs – pre-fuel snack 60 minutes before heading out, and stay hydrated. If the run exceeds 60 minutes (which is usually the maximum for these types of sessions), take a few jelly candies with you for an extra boost. – I do, and rather enjoy them on my rest intervals.
  • Long runs – Pre-fuel with a high carbohydrate meal 2-3 hours before your run. With a lighter (carb-filled) snack before you head out. (This would warrant waking up earlier for morning runners!) ensure you are also mindful of your hydration levels before the run and incorporate electrolytes. Whilst on the move, consume 30-60grams of carbs every hour (200-250 calories). This could be made more digestible with bites every 15-20 minutes, mind.
  • Avoid/limit protein, fibre and fat on the run
  • Opt for a variety of products such as gels or gummy candies, as usually, one serving provides within a region of 30-60g of carbs perfect!
  • *Please be aware of dieting supplements, as they usually lack in carbohydrates*


Eating after your run

You may have read that recovery is the most important part of your training plan. It’s where all your muscle healing and growth occurs, so best make sure we help the body out all we can eh?

Protein is responsible for repair and building of muscle, so ensuring you get enough but not too much; because there is no benefit.

What’s the optimal?

  • 0.4g per kg of BW 3-6x a day.

For example: our 70 kg friend needing 28g protein 3-6 times a day. (This 5 medium eggs, 30g whey protein, 150g tofu, or 100g chicken for example).

Counter to popular belief, “eating more protein will make muscles grow bigger and quicker” doesn’t occur. It’s all about timing. Within 30-45 minutes of finishing a run you need a recovery meal balanced with carbs and protein. Remember the parameters?

70kg friend would need a meal consisting of

  • Protein: 28g
  • Carbs: 140-223g
  • Immediately post-run I like to have a smoothie (fruit, spinach, oats, sunflower seeds and yoghurt or milk) or soya chocolate milk to replenish immediate carbohydrates and protein to start the recovery process).

    Man eating pasta

    Powers of natural foods

    • Ginger: a natural spice to add flavour, it also helps relieve much soreness and is a natural anti-inflammatory agent. Add to your main meals, os smoothies or even brew a ginger tea to aid recovery.
    • Turmeric – again another natural anti imflammatory. We add this to a lot of our meals especially when muscle soreness sets in.

    Now you know what to eat building up for your long runs, why not look further and discover what to eat for the build-up of your race day?

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