Run fuelling: A holistic approach

Dr Breanne Kunstler (BBiomedSci, BHealthSci, MPhysio, PhD).

Physiotherapist, behaviour change scientist and run coach.

There are people who insist on eating before a run to feel energised and prevent the dreaded mid-run "bonk" (no, not that kind of bonk...) and those who absolutely refuse to eat to avoid tummy upsets and hope for the best. Both of these runners will use stored carbohydrate, which comes from food consumed in meals consumed in the hours and days before the run.

Regardless of whether you eat before a run or not, your run is going to use carbohydrate/carbs (sugars) to fuel your muscles. Therefore, getting the most out of your running depends on the food you consume, and don't consume, at times when you aren't running too. Those who make sure they get sufficient carbohydrate in their diet throughout the days leading up to their run will likely get more out of their running.

Eating to run: How much carbohydrate should I eat each day?

There's plenty of evidence out there telling us that consuming sufficient carbohydrate is important in the days leading up to your run, in the hours leading up to your run, right before you run, during your run and even after your run! Carbohydrates are easily the most important fuel for runners, especially endurance runners (e.g. those doing 10km+ runs), to see them achieve their pace and/or distance goals. But scientists often use fancy terminology and numbers to tell us how much carbohydrate we should consume, which can make following their advice super tricky.

 
Science likes to give us numbers that are hard to interpret when advising us on how much carbohydrate we need to consume across the day. Sometimes the numbers refer to the amount of carbohydrate per kilogram of lean body mass, sometimes it's for complete body mass (e.g. 6-12g/kg). Advice based on these numbers can sometimes neglect the need for different fuelling strategies for different training days (e.g. easy vs hard). It is important that your carbohydrate (and other nutrients, like protein) intake differs based on the training you do that day.

This complexity makes running nutrition difficult. It's easier to just think in whole food items instead of numbers. So, lets do that, shall we?

What can we eat to make sure we are fuelling our runs with some good carbohydrates?

I'm going to share with you a simple experiment you can conduct to determine if you are getting enough carbohydrate in your diet to fuel your running.

Step 1: Eat real food and don't unnecessarily cut out food groups. Eat a normal, well balanced diet that consists of carbohydrates, fats and proteins and is based on the dietary guidelines for your country every day [Image 1].

Image 1: The foods that should be in a normal, healthy diet.

Step 2: Then test yourself over a series of runs.

Go for your normal run and, while you are running, monitor how you are feeling. Are you lacking energy or do you feel really comfortable, like you have the energy to keep going? If you feel like you can keep going comfortably then you are probably consuming the right amount of carbohydrate needed to fuel your runs and your everyday activities. Repeat this for each run over one or two weeks.

If you feel like you are lacking energy, "bonking", not able to maintain your pace or feeling like you won't reach your target distance then you might need to boost the amount of carbohydrate you are getting in your diet, especially around training days.

Step 3: Test a periodised nutrition approach. Use the Athlete's Plates for a week or two and see how your running changes.

Athlete's Plates give those who exercise a visual representation of what each meal should look like. Periodised means that your nutrition changes over days, and even within days, based on your nutrition needs. Simply put, using different plates based on your training load for the day results in you periodising your nutrition.

An easy training day*, or rest day, is the day where you heap those veges on your plate [Image 2]! That doesn't mean that you should be avoiding all carbohydrate and protein that day because your body still needs them for fuelling and repair, but you just don't require as many compared to a day where you train more or harder.

Image 2: The foods that should be in each meal on an easy or rest day

As your daily training gets harder, the percentage of each meal that is taken up by carbohydrate increases [Image 3]. So, basically, the harder the training session, the more carbohydrate you need to consume that day to ensure your body is fuelled enough to repair itself, function throughout the day (e.g. breathe, walk to the train, study) and be ready for your next training session. Note that the percentage of the plate taken up by protein doesn't change.

Image 3: The foods that should be in each meal on a moderate training day (e.g. relaxed run day)

Hard training days call for half of your plate to consist of carbohydrate [Image 4]. This can be hard for many people to do due to intolerances (i.e. FODMAPs), allergies (i.e. coeliacs) and lack of cooking skills that can lead to boredom (i.e. people who don't enjoy cooking might just eat heaps of pasta).

Harder training days call for a greater amount of energy to be consumed. So, hard training day plates also involve more snacks than easy days.

The amount of food some people (e.g. elite-level athletes, those training twice a day or those who expend a lot of energy in other tasks like pregnancy, breastfeeding and manual labour) need to consume can be so difficult they they might turn to unhealthy alternatives (e.g. cookies and cakes), make themselves feel unwell from overeating, consume sports drinks and other forms of supplementation or simply accept that they will be under-fuelling (which is very unhealthy and not advised).

Image 4: The foods that should be in each meal on a hard training day (e.g. long and/or high intensity run day)

*an easy, moderate and hard training day looks different for everyone. Test out each plate and see how your running responds. See this link for more information on this process.

So, should I increase the amount of carbohydrate I eat?

Maybe, maybe not. Everyone is different. I suggest seeing how your runs feel when you are following a normal, healthy diet [Image 1]. If you feel like you need more energy within or after your run, then try following the Athlete's Plates [Images 2-4] and see how your running feels.

Basically, the main point is to forget the numbers, eat real food and listen to your body! Everyone knows when they feel crap and when they feel good. Try the different fuelling approaches I've outlined above and see what works for you and your running.

Like this post? Check out my post on within-run fuelling (are gels the only go-to?)

Keep well, fellow runners!

Resources

Australia's guide to healthy eating can be found here

Calculate your daily energy needs based on your activity level, weight, age and sex here

View the athlete's plates here