FUELLING....Marathon Running - She Runs Eats Performs

Episode 93

Published on:

14th Apr 2022

FUELLING....Marathon Running

Fuelling....Marathon Running


Moving from moderate running to marathon running is a huge jump, and often runners forget to adjust their food plan accordingly. This can lead to a constant feeling of hunger, losing too much weight, getting ill or getting injured…all of which could affect performance. So, to help support YOU with your marathon running we answer the following questions:

Q1 – What is the aim/goal of nutrition for marathon running?

Q2 – How much and when do you need to eat pre and during a marathon

Q3 – What should you eat pre and during a marathon



Outlining the key goals of nutrition for marathon running including:

  1. Optimal Body mass and anthropometry (ie physical size, shape, form, and functional capacity)
  2. The body’s capacity to use macronutrients (particularly carbohydrate) to produce adenosine triphosphate (ATP – our energy currency) economically over the duration of the event
  3. Maintenance of reasonable hydration status – especially in the face of sweat losses induced by exercise intensity and the environment. Remember hydration is a limiting factor in running performance!!



Female runners tend to possess lower VO2max values than male runners and this is thought to be due to factors including: 

  • Males having Higher haemoglobin concentrations, which increases O2 delivery at the maximal cardiac output
  • Males generally having lower fat mass than females

NOTE: VO2 max is the maximum or optimum rate at which the heart, lungs, and muscles can effectively use oxygen during exercise.


Discussing a nutrition protocol in the days and hours leading up to a marathon with a focus on HOW MUCH and WHEN to eat including:

Days prior to a marathon event:

  • Carbohydrate loading protocol beginning 36–48hrs prior to the event 
  • Consuming carbohydrate in levels between 6-12g/Kg BW/d. This will be very individual
  • Should this protocol be undertaken in conjunction with a low residue (fibre) diet?

Hours prior to a marathon event:

  • Consuming a meal containing between 1–4 g/kg of Body Weight of Carbohydrate
  • Consuming a carbohydrate rich meal between 1-4-hrs pre-race. 
  • Should this meal be low fibre and contain limited protein and fat?

Immediately before a marathon event:

  • Consuming a quick release Carbohydrate rich snack
  • Consuming the snack approx. 30mins before the event 


Outlining WHEN and HOW MUCH to eat DURING a marathon event including: 

  • Consuming quick release CHO rich foods throughout
  • Carbohydrate content of food being between 30-60g  
  • Consuming a snack every 45–60 mins.


Focusing on WHAT to eat in the days and hours leading up to a marathon event, with some comments on a low vs high fibre diet at this time

Foods to eat in the days prior to a marathon event:

  • Wholegrains
  • Root vegetables
  • Lean Protein
  • Plant-based protein
  • Non-root vegetables

Foods to eat on the morning of a marathon event:

If there is 2-4hrs before the race then consume 2-4g/Kg BW respectively of CHO food sources

  • Wholegrain and root vegetables as carbohydrate choices at this time
  • Lean protein sources
  • Plant-based protein
  • If there is less than 2hrs before the race quick release CHO foods are recommended e.g. white bread, white rice, polenta, white potato

Foods to eat 30mins before a marathon event:

  • Medjool dates
  • Raisins
  • Banana
  • Ella’s Kitchen pouches


Outlining WHAT to eat during a marathon event:

  • Medjool dates
  • Raisins
  • Ella’s Kitchen pouches
  • Natural bars or gels e.g. Honey Stinger, Veloforte, Tribe



  1. It is really important to consider your nutrition and food intake when running a marathon….especially your CHO intake 
  2. The key aim of nutrition for marathon running is efficient energy production throughout the event and CHO is the principle macronutrient to achieve this
  3. Remember, CHO is one of the limiting factors in exercise performance, with hydration being the other one
  4. Race-day nutrition needs to begin in the few days leading up to the race as well as on the morning of…and during the event…..all of these protocol timings are equally important for peak performance
  5. The guidelines suggest a low fibre protocol in the days leading up to a marathon but, although this approach may have some advantages, it also has several disadvantages including: A reduction in micronutrient density, food cravings and poor food choices
  6. FINALLY…..PRACTICE during training…..practice, practice, practice is the key to success

Related Topics

Race Day Success: Nutritional Strategies

Nutrition for Half Marathon Plus

Your Marathon: Run-Refuel-Recover


The suggestions we make during this episode are for guidance and

advice only, and are not a substitute for medical advice or treatment.

If you have any concerns regarding your health, please contact

your healthcare professional for advice as soon as possible.

Aileen Smith and Karen Campbell met at as nutrition students (Institute for Optimum Nutrition, London) and became lifelong friends and nutritional buddies! Both have a love of running and a passion for nutrition, delicious food and healthy living.

Together they host RUNNERS HEALTH HUB. A place for like-minded runners who are looking for simple ways to support running performance, energy, endurance, and general great health.

We are excited to be able to share our expertise, experience and short cuts with you. We hope you'll join us again. If you'd like to know more about us and She Runs Eats Performs please check out our TRAILER.

If you're ready to make learn more about how you may introduce easy nutrition into your running and training plan join our Easy Nutrition For Healthy Runners Online Programme for short videos, recipes, downloads and LIVE training and Q&A.

As a THANK YOU to you as one of our valued listeners, we have a special offer for you use COUPON CODE POD to get 33% discount off the full price which brings the price to £199.

If you’d like help from Karen and Aileen to design a personalised sports nutrition plan for your running - please contact them at hello@runnershealthhub.com

Happy Running!

Aileen and Karen



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About the Podcast

She Runs Eats Performs
for mid-life female runners of all abilities
Are you confused about the science around nutrition for runners? Listen in to learn about the WHY, HOW, WHAT, and WHEN of eating to fuel your running performance.

We are here to help you translate sports nutritional science, into easy to apply tips and plans, helping you enjoy peak running performance. We focus on the FEMALE FACTORS every mid-life woman needs to know to be a healthy runner.

About your host

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Aileen Smith

Nutritionists, Educators, Podcasters, Runners and Friends

We have a love of running and a passion for nutrition, delicious food and healthy living. She Runs Eats Performs for female runners of all abilities who are looking for simple ways to improve their running performance and their health with nutrition and lifestyle.
We enjoy sharing our nutritional expertise, reviewing the latest sports science and most of all helping you to take easy action so you can enjoy your running life to the full.
We are here to help you achieve great health and good shape whilst staying injury-free with easy-to-understand sports nutritional concepts and easy-to-implement tips and plans.

Aileen and Karen are BANT and CNHC Registered Nutritional Therapists.