Pre-performance
Pre-performance nutrition is about preparing the body for exercise. There are a number of important considerations for athletes to be aware of as part of pre-performance nutritional strategies. These include:
- what type of food to eat and in what amount
- when to eat and drink and
- how to carbohydrate load if required.
Food consumed prior to activity is useful only if fully digested and its energy and nutrients available to where they are required in the body. Fluid levels rarely keep pace with the body's requirements, and they need to be repeatedly replaced.
Type of food
As carbohydrate is the primary fuel source for exercise of
moderate to high intensity, optimising carbohydrate levels in the muscle and
liver is the primary goal of pre-performance preparation. Foods higher in fat
and protein and fibre require longer periods to digest than most foods. This
may lead to discomfort and possible indigestion if consumed close to activity
or in large amounts. Liquid meals (drinks with high carbohydrate content) are
sometimes recommended for athletes. Athletes are advised to eat mostly complex
carbohydrates, such as wholegrain cereals, such as bread, pasta and rice,
because they have a low glycaemic index (GI) 
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that is, provide slow energy release.
Amount of food
Generally, the appropriate amount of food relates to the expected energy expenditure of the event. This will vary with the type of activity and level of competition, e.g. competitors in endurance events need more energy over a period of time than events requiring short sharp bursts of anaerobic energy. Care needs to be taken that large amounts of food are not eaten prior to any event as it may cause gastrointestinal discomfort, particularly if the activity is of high intensity.
When to eat
Most athletes feel comfortable having a meal 3 to 4 hours prior to competition. If the time period before the event (or between games/events) is shorter, food intake should be in the form of snacks and liquid preparations.
Hydration
Hydration is important for all individuals, however for athletes, and especially those involved in endurance events or competing in hot or humid conditions, it is of extreme importance. As a general rule, 500-600 mL of fluid should be consumed in the 2 to 3 hour period prior to endurance performance and 250-350 mL in the last 15 minutes.
Athletes competing in endurance events or those that last longer than an hour may benefit from including sports drinks in their pre-performance preparation. The weather conditions on the day need to be considered carefully when planning fluid intake. High levels of humidity can extract a significant toll on athletic performance.
Carbohydrate loading
There has been much debate about the effectiveness of carbohydrate loading. Theoretically it aims to maximise glycogen stores prior to performance therefore gaining a competitive edge.
Carbohydrate is the preferred source of energy for the body therefore athletes increase the amount of carbohydrate they consume leading up to an event in the aim of maximising the body's storage of glycogen. The higher the levels of muscle glycogen, the greater the endurance of the muscles during performance.
The process of carbohydrate loading has been modified in recent years as the ability of individuals to go through glycogen depletion then glycogen loading had numerous negative effects on the athlete. New techniques involve consuming a diet high in carbohydrates and tapering training for two to four days before competition, causing glycogen supplies to be at maximal levels.
It is also believed that athletes involved in short-term, low-intensity activities do not need to carbohydrate load as a normal diet should provide adequate amounts of glycogen.
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The following websites will assist your understanding of carbohydrate loading.
Test your knowledge by completing the following questions.
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Further reading on pre-performance nutritional considerations can be found on the following websites.
- Sports Dietitians Australia:
Eating and drinking before sport
- Australian Institute of Sport: Eating before exercise
- Australian Institute of Sport: Nutritional tips on
preparing for elite competition