Fueling right for marathon or triathlons

So you've entered into your triathlon or marathon event for this year. You've put together your training plan. Have you put together a nutrition plan too? Nutrition is often a key element of a training plan that is overlooked.

Fueling right throughout your training and during your event, is key to performance. If you don't get it right, or if you don't practice a fueling plan during your training, this is when things can get sticky. Have you ever heard of the terms 'hitting the wall' or 'bonking'? This is down to dehydration and depletion of all your energy (Glycogen stores).

If you sacrifice so much of your time on training, it's only fair to your body to fuel it with what it needs. It doesn't have to be complicated, or time consuming. Get yourself into a little routine for pre, post and during your training sessions.

Below are some of my key nutrition tips from that have worked throughout past endurance events and studies to be a personal trainer


Top Tips

  • Your body stores carbohydrates in your muscles in form of Glycogen.
  • During your long runs you need to replace your glycogen stores every 40-60 mins- ideally with gels. ‘Hitting the wall’ means you are depleted of all your glycogen stores.
  • Eat 1-2 hours before workout
  • It’s important to fuel exactly the same way you fuel during training, during the marathon. Your body will adapt to what you do during your training so don’t differ.
  • A low GI (glycemic index) carbohydrate means that the food is broken down slowly and enters gradually into your bloody stream. Meaning slow release energy.
  • The night before your long run - don’t over eat. Carbs would be good but just a normal portion. A mistake a lot of people make is over eating when training.

See below for my tried and tested pre, during and post training nutrition plan


PRE session FUEL

  • Ensure you are properly hydrated.!
  • Eat a low GI carbohydrate meal 1-2 hours before workout.
  • Coffee is great before training! Many studies showing how it improves performance
  • Recommendations:
  • Coffee
  • Porridge Oats with almond milk with almond flakes, honey, banana (add nuts, dried fruit)
  • Ensure you are properly hydrated.

<Low GI Breakfast Recipes>


You will be depleting your glycogen stores during your long runs. So replacing you glycogen stores every 40-60 mins with gels is recommended. Listen to your body and see you you feel during the run. I normally take my first gel after an hour, then every 45 mins after that.

No need to refuel with gels during your mid week shorter runs (60 minute or less runs).

Rehydrate with electrolyte fluids (you lose your electrolytes through sweating in form of salt. Quite often why you get cramp, lack of salt in your body)



Electrolyte tablets



It’s essential to refuel your body correctly after workout to aid recovery, avoid injury and promote muscle repair and muscle growth. I would recommend protein shake within 30 minutes after the run as soon as you get in from the run. Then after an hour (once you’ve showered etc) make yourself a meal full of carbs & protein.

Consume protein within 30 minutes of your training session. This is when your muscles are at it’s optimum to absorb protein for growth, it’s a key window. I’d always recommend a protein shake as it’s an incredibly quick and easy way to consume protein instantly.

After training you will need to top up your glycogen stores which would have been depleted through the run. So make sure you consume a meal with protein & carbs (in addition to point 1).


  • Protein Shake with almond milk straight after run (within 30 mins)
  • Glass of orange juice to replace your glycogen stores.
  • Wholemeal Toast, with peanut butter and banana
  • Muffin/toast with eggs and spinach
  • Thicker protein shake - porridge oats, yoghurt banana, nuts, peanut butter, protein shake

Here’s a good link for - Post Workout Recipes

Low GI Carbs:

  • Whole grain bread
  • Porridge oats
  • Basmati Rice
  • Beans, Lentils & Nuts
  • Carrots
  • Milk
  • Yoghurt



  • Meats
  • Fish
  • Milk
  • Yoghurt
  • Cheese
  • Beans
  • Chickpeas
  • Nuts
  • Seeds - Sesame, sunflower
  • Peanut butter

High GI Carbs:

  • Bagel/baguette
  • Brown Rice
  • Baked Potato with skins
  • Fruit Juice


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