# Healthy eating habits/Eating Carbohydrates to optimise sprint training and athletic performance

The following page provides a guide on the role carbohydrates play in high intensity sprint training and how best to eat carbohydrates to boost athletic sprint performance.

## The Importance of Carbohydrates

Carbohydrates is the main fuel source used during sprint training and high intensity exercise. The body stores a limited amount of carbohydrates in the muscles for high intensity exercise.If muscle carbohydrates stores are to low to meet the bodies fuel needs it can cause muscle fatigue, decreased immune system functioning, reduced ability to train at high intensities and decreased competition performance. To avoid these negative effects athletes should plan their carbohydrate consumption around their training schedule and base meals and snacks eaten throughout the day on carbohydrate rich foods.

## How much carbohydrates do sprint athletes need to consume

Carbohydrate intake levels vary depending on the individuals number of training sessions per day, intensity and duration of training sessions, and the height and weight of the athlete. Since activity levels change from day to day, daily carbohydrate consumption should be increased or decreased to match the daily activity demands of the athlete. This will help get the most out of every training session and also promotes optimal recovery between sessions.

## Types of carbohydrates

Carbohydrate foods can be split into two categories that describe the speed at which the food is digested and absorbed by the body.

### High GI/Simple carbohydrates

These carbohydrates are easily digested and quickly absorbed by the body which provides muscles with a quick short burst of energy. Simple carbohydrates include foods that are typically highly refined and high in sugar.

#### Examples of High GI/ Simple carbohydrates

white bread, dry biscuits, fruit, lollies, sports drinks

### Low GI/ Complex carbohydrates

These carbohydrates are broken down and absorbed by the body at a much slower rate and provide the body with a more steady supply of energy that lasts for a longer period of time compared to simple carbohydrates. Low GI foods should make up most of the carbohydrates in an athletes diet as they help keep individuals feeling fuller for longer and deliver a more sustainable supply of energy. Low GI foods include less refined foods such as wholegrains and are typically lower in sugar and higher in fiber compared to simple carbohydrates.

#### Examples of Low GI/ Complex carbohydrates

wholegrain bread, wholegrain cereal, pasta, kidney beans, sweet potato

## Eating carbohydrates before training

Eating carbohydrate rich foods before exercise can help boost energy levels and top up muscle carbohydrate stores. When choosing food to eat before training it is important to time your food intake so that the fuel has enough time to be broken down and absorbed by the muscles.Ideally a complex carbohydrate food should be eaten 3-4 hours before training as this will allow enough time for proper digestion. The complex carbohydrate food should make up 70% or 2/3 of the total meal/plate. However eating 3-4 hours before training may not always be possible, especially if training sessions are held early in the morning. If this is the case a lighter meal/snack should be eaten 30 minutes before training. Foods that are high GI and contain simple carbohydrates are the best choices as these are digested quickly so decrease the risk of indigestion during training and provide energy to the muscles at a faster rate.

#### Foods suitable to eat 3-4 hour before exercise

* 1 bowel of cereal such as oats or natural muesli
* 1 wholegrain sandwich
* 1 cup of mashed sweet potato
* 1 bowl of pasta with tomato-based pasta sauce

#### Foods suitable to eat 30 min before exercise

* 1 muesli bar
* 1 jam/honey sandwich made with white bread
* 1 piece of fruit such as banana or orange
* 300ml of sports drink

## Eating Carbohydrates after training

Carbohydrates play an important role in muscle recovery after training because during high intensity exercise the amount of carbohydrates in the muscle decreases.Therefore it is important to replace carbohydrate stores before the next training session in order to perform at your best.A carbohydrate rich snack should be eaten within 30 minutes of completing exercise as this is when carbohydrate absorption in the muscles is at its greatest. This snack should also contain a small amount of protein as this helps boost carbohydrate absorption into muscles which speeds up the recovery process. Incomplete or delayed carbohydrate replacement after training reduces the muscles ability to perform well at the next training session and can lead to fatigued muscles resulting in decreased physical performance.

#### Foods suitable to eat 30 min after exercise

* 1 small tub of yogurt
* 1 sandwich with a protein rich filling such as peanut butter, chicken or egg
* 1 bowl of cereal and milk
* 1 cup of flavored milk

## Useful resources

Sports Dietitians Australia Factsheets
AIS Carbohydrate Fact sheet

## References

Australian Institute of sport. (2009). Nutrition: Competition and Training. Retrieved from http://www.ausport.gov.au/ais/nutrition/factsheets/competition_and_training
Maughan, R.J., & Burke, L. (2002). Sports nutrition. Malden, Mass: Blackwell Science.
Sports Dietitions Australia. (2013). Fact sheets for the general public. Retrieved from http://www.sportsdietitians.com.au/factsheets/
Thomas, B., & Bishop. (2007). Manual of dietetic practice (4th ed.) Oxford, UK: Blackwell Publishing Ltd.