Distance runners will often run lengths between 10km to 42.2km marathons. This therefore requires appropriate nutrition for optimal performance and recovery. This is particularly important if the distance requires a run, opposed to undertaken at a more relaxed pace for those who partake in runs for the social/fun aspect.
Elite runners will characteristically have a low body weight, small stature, lean muscle and low body fat levels. This structure is ideal as the runner has less weight to carry over a long distance. Excessive amounts of muscle or body weight will weigh the runner down.
Factors related to nutrition that encourage fatigue and hinder performance:
- Depleted muscle glycogen stores
- Hypoglycaemia (low blood sugar levels)
- Hyponatremia (low blood sodium levels)
- Dehydration
- Gastrointestinal upset
Training/ pre- race diet
Pre-race dietary interventions are designed to decrease the risk of factors occurring that will affect peak performance e.g. insufficient fuel/ fluid supplies or GI discomfort. These dietary measures are usually implemented as early as a week prior to the event and are continued even up to minutes before the race.
Carbohydrate intake
The most important dietary component for distance runners is adequate carbohydrate intake. A diet too high in protein and fat can displace carbohydrates and hence not allow for the maximum replenishment of muscle glycogen stores [1]. This can negatively impact performance and recovery.
Preparation is therefore focused around optimising muscle and liver glycogen stores and minimising muscle injury. To reach peak glycogen storage leading up to the event, carbohydrate intake needs to be increased and exercise should be tapered [1].
As the duration and intensity of the exercise increases, the requirement for fuel (carbohydrate) also increases [1]. For this reason, specific advice cannot be provided. Exact requirements will vary depending on the individuals training routine and the event to be raced. Lighter training days will require a lower intake of carbohydrate than heavier training days [1].
Choosing carbohydrate rich foods can make it easier to meet requirements.
For events 60-90 minutes in length: Twenty four to thirty six hours of rest and adequate carbohydrate intake (7-10g/kg per day) should adequately replenish carbohydrate stores during training [1]. For these events, carbohydrate loading does not appear to be beneficial and can lead to weight gain.
Only light training should be performed the day prior to the event [1]. Energy restrictions should also be lifted during this time in order to meet carbohydrate requirements for adequate glycogen stores – this can be difficult for individuals that are concerned with gaining body weight.
Endurance events over 90 minutes: These events will require a carbohydrate loading phase [1]. This is to ‘supers compensate’ muscle glycogen stores prior to the event, which helps to prevent the depletion of fuel reserves during the race. A high carbohydrate diet for 3-4 days prior to the event will saturate muscle glycogen stores, prolonging time to fatigue during training/ the event [1].
Often athletes do not have the appropriate knowledge to successfully taper exercise or reach carbohydrate targets [1]. For this reason, seeing a sports dietitian can be beneficial.
Post training recovery
Running will deplete carbohydrate stores and cause some muscle damage. For these reasons, it is important to refuel with carbohydrate rich foods soon after training. This will replenish glycogen stores within the muscles and liver. Appropriate post exercise nutrition also helps to build and repair muscle and reduce any injury or fatigue [2]. A small portion of protein will assist with recovery and muscle building. The post training intake therefore supports training adaptation and prepares the body for following bouts of training and events [2].
Your requirements for glycogen replacement will also be dependent on muscle mass, the individuals training routine and what the remainder of your dietary intake is like [2].
Carbohydrate
Post-training recommendations: It is recommended that athletes consume around 1.2g of carbohydrate/kg of body weight within the hour following exercise and for the following four hours post exercise [2]. Regular carbohydrate intake (to meet daily requirements for the individual) is then adequate [2].
Protein
Active muscles deplete amino acid stores. This is what protein is made up of. Therefore, protein is another important nutrient post-training as it can reduce the breakdown of muscle [2]. Once again, individual requirements can vary quite significantly.
Post training recommendations: As a general guide, 20-25g of protein should be consumed as soon after exercise as possible [2]. This will assist with muscle building and reconditioning.
Recovery snack options
A meal or snack including both carbohydrate and protein is recommended post exercise. Low fibre carbohydrate options are advised as they are absorbed more quickly. The ratio of carbohydrate to protein should be 3:1 [2].
Suitable recovery options for athletes:
- Toast with baked beans
- Cereal with milk
- A piece of fruit and a bread roll with lean meat or cheese
For the average person who only exercises half an hour a day, at lower intensities, the regular dietary guidelines should be followed in order to meet nutrient requirements [2]. Any additional high carbohydrate or protein snacks post work out will only increase energy intake and possibly lead to weight gain. Timing meals after workouts may rather be more effective [2].
For more information
References
- Burke L, Deakin V. Clinical Sports Nutrition. Fourth Edition. Australia: McGraw-Hill Australia Pty Ltd; 2010.
- Health Check: tips on eating to recover after exercise.
Contact us for results focused nutritional advice
This article was written by our dietitian Belinda Elwin who is a Dietitians Association of Australia member and Accredited Practising Dietitian and Nutritionist.
If you have questions about exercise and nutrition or other nutrition related issues, make an appointment. We‘ll provide you with a simple and effective routine targeted to your concerns.
