Print Friendly, PDF & Email

Carbohydrates in Sport

Carbohydrate is a key fuel source for exercise, especially during prolonged continuous or high-intensity exercise. The body stores carbohydrate as glycogen in the muscles and liver, however its storage capacity is limited. When these carbohydrate stores are inadequate to meet the fuel needs of an athlete’s training program, the results include fatigue, reduced ability to train hard, impaired competition performance, and a reduction in immune system function. For these reasons, athletes are encouraged to plan carbohydrate intake around key training sessions and over the whole day according to their carbohydrate requirements as an exercise fuel. (Source: AIS website, June 2017)


For decades athletes have been using GI science for their sports preparation and recovery. Low GI foods have proven to extend endurance when eaten 1 – 2 hours before prolonged strenuous exercise.

Eating to maximize your sports performance:


The night before the event.
Planning ahead for a morning event, your evening meal should contain more carbohydrate than you would normally have.  This is so you can fill up your glycogen stores. The carbohydrate should be low GI and the whole meal should be lower in fat, moderate in high quality protein and comfortable in quantity.  Don’t over eat!

Foods to avoid just before exercise.
The following foods may cause stomach discomfort due to their typically slow digestion:

  • Any food high in fat
  • High fibre foods: white and some whole meal breads are acceptable – check the label
  • High protein.  Make sure your protein intake is moderate to low, as it may also cause discomfort by slowing the rate of emptying from your stomach.

Breakfast on the morning of the event.

This should be carbohydrate based, low fat and moderate in protein.  Exactly what to eat, will depend on the time between breakfast and the start of the event.  The following table will give you a breakfast guide based on your start time.  As with dinner you should only eat a comfortable amount of food, otherwise you will regret it!

Suggested pre-exercise breakfast foods

2-4 hours before the event – normal volumes

1 hour before event – smaller volumes

  • Low GI breakfast cereal + skim milk.
  • Burgen® bread with Jarrahhealth™ honey.
  • Tip Top® 9 Grain™  bread with jam.
  • Raisin toast plain or with jam/honey.
  • Fresh fruit with skin on: stone fruit or pears, apples, grapes, grapefruit.
  • Low fat yoghurt.
  • Small skim banana smoothie – no ice cream.
  • Fresh 100% orange or apple juice.
  • Grain and fruit based bar.
  • Milo® with reduced or low fat milk.
  • 100% fruit juice.
  • Canned fruit in juice.
  • Small amount of low GI. breakfast cereal  with reduced fat or skim milk.
  • Sustagen® or Sanitarium™ Up & Go™  Energize.

During event and recovery foods.

During the event you should consume high GI carbohydrates – fluids like Gatorade® and Powerade® are often ideal.

One to 2 hrs after an event your food and fluid choices should be Low GI.  Your body needs to replenish its glycogen stores, and delaying this replenishment can lead to fatigue.  Replenishment of carbohydrate is generally 1 gram carbohydrate per 1kg body weight.  So a 75kg man needs 75g carbohydrate for recovery after the event.  Some suggestions for foods for during the event recovery foods and volumes are below.

Some suggestions for foods during and post an event.

During event – High GI

Recovery – Low GI*

  • Gatorade® or other sports drink.
  • Goo or liquid glucose supplement.
  • Jelly beans, snacks, sugar lollies.
  • Cordial.
  • White bread with regular honey.
  • Scones.
  • 5-6 slices Low GI bread like Burgen®, Tip Top® 9 grain™ or Helga’s™ Lower Carb bread.
  • 2½ cups low GI breakfast cereal with reduced fat milk.
  • 1 ½ cups cooked Sunrice® Doongara™ low GI brown or white rice.
  • 850ml 100% fruit juice.
  • Milo® with reduced-fat milk, Sustagen® or Up & Go™ Energize drink.

*Suggested volumes provide 75g carbohydrate for 75kg person


for the latest news on the glycemic index, certified low GI food products,
and low GI recipe inspiration.

You have Successfully Subscribed!