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Nutrition for Adventure Racing / Triathlons

Category: Sports and exercise nutrition
Sports and exercise nutrition

Adventures races are endurance races that cover a variety of distances, durations and terrain. These events are usually 'continuous' and all adventure races include more than one discipline, commonly trail-running, off-road trekking, mountain-biking and kayaking or canoeing. Adventure races differ greatly so you should research the event requirements. They are scheduled throughout the year so competitors should choose their key races and allow sufficient time for recovery between their chosen events. Some well known adventure races in Ireland include Gaelforce, Achill ROAR and Killarney Adventure Race.

Routine endurance training increases your daily energy (calorie), carbohydrate and protein needs.  Failure to meet your daily nutrient needs can lead to persistent fatigue, poor recovery, illness, and unwanted weight loss. For this reason, a diet and hydration plan that meets your nutrient and fluid needs are vital to performing at your best.





Carbohydrate is the most critical fuel source for adventure race training. Carbohydrate is stored in the liver and muscles as glycogen. Fuel stores are limited so regular replenishment is essential. A diet high in carbohydrate is essential to keep these levels topped up.

Good sources of carbohydrates include:

  • Bread/Baps/Rolls
  • Cereals
  • Potatoes/Pasta/Rice
  • Dairy foods; milk and yoghurts
  • Fruit
  • Sweets and jams
  • Scones/Crackers/Fruit cake
  • Sports drinks and gels

Depending on volume, frequency and intensity of training, daily carbohydrate requirements range from 8-12g/kg body weight.



Protein needs are also heightened to meet daily protein turnover needs and assist in muscle repair.

Good quality sources of protein include:

  • Meats
  • Poultry
  • Fish
  • Dairy foods
  • Nuts and seeds
  • Peas, beans and lentils
  • Eggs

To meet high requirements, ideally these should be consumed at every meal. For example, a dairy product in the morning, some meat and nuts at lunch time and a lean meat in the evening. Protein supplements may also be used, but should be considered in line with overall goals. Great foods to use around exercise include both protein and carbohydrate, such as a dairy snacks, peanut butter sandwiches or nut-containing muesli bars. Daily requirements for protein in athletes range from 1.4-1.7g/kg body weight.


Fruit and Vegetables

At least five portions of fruit and vegetables per day should be included in the diet to ensure the athlete meets their daily vitamin and mineral needs.

To recover from training and to replenish fuel stores for the next training session, you should eat after training. 1-1.5g of carbohydrate per kilogram body weight should be consumed within 30 minutes of exercise where possible and a small portion of protein (e.g. 0.2g per kg body weight) is ideal.


Top tips For Your Training Diet

  • Increase the number of eating occasions (6-8 times /day). Base all meals and snacks around the following foods which are high in carbohydrate.
  • Reduce your intake of high fat foods e.g. chocolate, cakes, fried foods, full fat cheese.
  • Training is a good time to experiment with the type and timing of food you consume before running in order to avoid any digestive discomfort like stomach cramps, diarrhoea or wind.
  • It is important to trial different carbohydrate replacement drinks (sports drinks, gels, bars etc.) during your training to make sure that they do not upset your stomach or give you diarrhoea.
  • Remember isotonic/sports drinks will provide fluid and top up your daily carbohydrate intake.
  • Remember to choose a snack containing both carbohydrate and protein within 30 minutes of stopping training (see post exercise snack list).
  • Ensure adequate rest in between your training sessions.


Fluid Needs

During training you will lose fluid through sweating. Unless those fluid losses are replaced by drinking (sports drinks/water), you run the risk of becoming dehydrated which can cause fatigue and impair your performance.

Maintaining hydration levels throughout the event can be a challenge. Particularly in hot conditions it can be easy to become dehydrated. It is important to evaluate your sweat losses and fluid needs during training. Competitors may need to balance carrying weight with minimum water intake requirements due to the carrying capacity of fluids for long sections without refill possibilities. Training is a good opportunity to practice fluid replacement. Suitable drinks during training include water, diluted fruit juices and sports drinks.


Pre Event

  • Ensure your last meal the day before the event is high in carbohydrate with a lean protein source. Eat what worked for you during training and avoid trying new foods at this late stage.
  • A high carbohydrate, low fat, low fibre meal should be eaten 2-3 hours before the event, for example: Extra snacks can be taken before the race to boost your carbohydrate (cereal bars, isotonic drinks/yogurts).
    • Cereal (muesli/porridge/cornflakes) and low fat milk
    • And/or white bread toast with low fat spread and jam/marmalade
    • Fruit/Fruit juice
    • Low fat yoghurt
  • Ensure you start the event fully hydrated. A general guide is to drink 400-600ml in the 2 hours leading up to the event.


During the Event

  • Take 30-60g of carbohydrate every hour e.g. 600 – 1000ml isotonic drink, 1.5-2 packets gels or 40-75g dried fruit (or a combination of these).
  • Experiment with what works for fuelling during training and find out if fluids/gels will be available during the race so you can experiment with these brands in training.
  • During the bike leg in an adventure race is a great opportunity to eat compared to the running leg.
  • Fluids – a general guideline is to drink 150-200ml every 15 minutes. The aim is to lose no more than 2% of your body weight during exercise (e.g. 1.5kg for a 70kg person). For endurance events there is a rare chance that a competitor could drink too much with potentially fatal consequences. If you are exercising for more than four hours in hot weather, drink no more than 800ml per hour, be guided by thirst and sip a sports drink that contains sugar and salt instead of plain water.
  • Evidence suggests that caffeine improves endurance. 1.5mg/kg taken in divided doses throughout an intense workout has been shown to benefit performance (e.g. 4 caffeine containing sports gels over two hours). Caffeine’s side effects include sleeplessness, trembling and anxiety. So if you are sensitive to caffeine, it is best you avoid it.



  • Ensure a snack or meal high in carbohydrate and protein is taken within 30 minutes of finishing the race:Make sure to take high carbohydrate meals and snacks for the next 24 hours after the race.
    • Flavoured milk, apple and muesli bar
    • 600ml sports drink and cereal bar
    • Banana and low fat fruit yoghurt
    • Breakfast cereal, low fat milk and dried fruit
    • Sandwich/roll/wrap filled with chicken/ham/egg/tuna
    • Jacket potato with tuna/baked beans/low fat cheese
    • Baked beans/spaghetti on toast


Other Tips

  • Having a backpack/Camelbak/race belt will help carry your food and fluids for the event
  • Wearing a cycling jersey with rear pockets to carry additional fuel/gels
  • Leave food and drink in transition areas if possible
  • Fit additional bottle cages on your bike to carry additional fluids


Sample Training Diet:


Time Meal

Breakfast cereal and low fat milk


Fruit juice

Training run

Isotonic drink

Post training

Low fat yoghurt and fruit

Fruit juice/flavoured milk/sports drink


Wholemeal bread/bap/roll and low fat spread

Chicken/Ham/Tinned fish/Egg

Fruit juice

Slice of fruit cake/Banana cake/Cereal bar



Potato/Pasta/Rice (Half of plate)

Salad and low fat dressing/Vegetables

Glass of low fat milk

Fruit salad


Weetabix and low fat milk

For more detailed expert advice you can contact a sports dietitian through the Irish Nutrition and Dietetic Institute;


Created by Joanne Walsh, MINDI, BSc (Hons) Human Nutrition, Dip Dietetics October 2013, reviewed by the SNIG April 2016, Review date: April 2019

© 2016 Irish Nutrition and Dietetics Institute, INDI. All rights reserved. May be reproduced in its entirety provided the source is acknowledged. This information is not meant to replace advice from your medical doctor or individual counselling withadietitian.  It is intended for educational and informational purposes 

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