Nutrition

Just what do athletes need in the way of nutrition?

There is no magic food which if taken the day or several days before a race will transform the athlete into a world beater. So choosing a diet which provides the athlete with the correct balance of nutrients is desirable. The food and drink which athletes consume provide the energy for competition and training, aids recovery and ensures that their metabolic progress functions properly.

Before we consider athletes eating habits lets consider each of the different nutrients in our food:

1. Carbohydrate - the body preferred source of energy
2. Fats - another source of energy and a carrier of certain vitamins
3. Protein - essential for growth, repair of tissue and metabolism
4. Vitamins - essential for the body's metabolism
5. Minerals - essential for the body's metabolism
6. Fibre - essential for health of the digestive system
7. Water - as 60% of the body is water this needs to be replaced regularly.

So the athlete is in peak condition training and running well, feeling strong but is also tired because s/he cannot sleep and has muscle cramps, twitches and the trembles. This is probably due to the fact that the athlete's running and eating do not balance each other correctly. Many athletes and coaches are beginning to realise the need to understand more about nutrition. In order to plan a suitable food intake it is necessary to understand a little basic nutrition.

So where does the lay person find that knowledge?

A text book on diet/nutrition might seem a logical place to start but most athletes and coaches (and many other people) could be a little confused by Glucose (C6H2O6) being degraded to Pyruvic acid (2CH3 COCOOH) combining with 5 Oxygen molecules to form 6CO2 + 4H2O and ENERGY. The basic principle for athletes is there - glucose forming energy, but this equation is not really going to help anyone to plan a days food.

Lets consider the 7 nutrients

Energy

Usually referred to in terms of 'calories'. Many athletes need to consider their energy intake and make sure that sufficient energy is being consumed to cope with the energy expended in training. It is also important to make sure that the calories are coming from the right kind of foods.

Protein

Most of us actually eat more protein than we need. As well as the traditional sources of protein such as meat, fish, eggs, cheese, do not forget the vegetable proteins such as beans and pulses such as lentils.

Fat

We all tend to eat too much fat, especially the fat from animals. There is a general need to cut down by eating less fried foods, chips, crisps, pastry etc., and take the extra calories from starchy foods.

Carbohydrate

This is the term used for the starchy foods. Carbohydrates are a very important source of energy for athletes. Refined starches are those that have been highly processed such as sweets, cakes, sugar and white flour products. The more complex starches such as wholemeal bread and pastas and brown rice are important source of energy as well as other nutrients.

Fibre

Found in wholemeal products, fruit, vegetables, nuts, beans, etc. Important for functioning of the gut and bowel. The foods that contain fibre also contain many minerals and vitamins.

Vitamins

Those people taking sufficient calories and a wide variety of foods should not have problems with vitamin deficiencies. However, some vitamins are important for energy production and care should be taken to ensure an adequate intake.

Minerals

Again deficiencies are unlikely in a healthy diet. Some, especially iron, may need special consideration.

Dietary Rules

Many athletes ignore simple dietary rules. Their needs are greater than the average, not necessarily more but more selective. Five full cups of vegetables, fruits should be taken daily to provide the right amount of vitamin C, B and A. Three helpings of cereal or bread (four slices of bread is a helping), to provide roughage and carbohydrates. Two meat meals a day to provide iron. Fried food should be kept to a minimum. The athlete needs some fat but not the saturated kind found in bacon and too fatty meals. In the summer the potassium level is important. The heart is predominantly saturated with potassium.

There is no evidence that dietary supplementation with vitamins, minerals or other additives is effective in improving performances in any athletic event, except in the rare case of an individual suffering from specific deficiency. There is a great danger that supplements may supplement the natural nutrients that a competitor needs and hence contribute in some nutritional deficiency.

The same applies to dietary protein intake. In spite of the conviction common against athletes engaged in strength events, that a high protein intake is necessary for the athlete in serious training, total energy intake is high and together with this large food intake normally comes a more than adequate supply of all essential components.

The only dietary constituent which may be of vital importance to the athlete is carbohydrate. The high intensity effort performed in training will result in depletion of the muscle glycogan stores. If these stores are not replenished between training sessions, fatigue will ensure. It is therefore essential that dietary carbohydrate intake should be adequate for this purpose. If the dietary carbohydrate content is high it should be possible for the muscle glycogen stores to return to normal within 24 hours, also it replenishes to the point of 60% completion after 10 hours and total return after 46 hours.

There is some evidence that consumption of a very high carbohydrate diet 3-4 days before a race, together with a reduction in training intensity may be effective in improving performances by increasing the capacity for energy production by aerobic glycolysis. This carbohydrate loading procedure is used by athletes engaged in endurance events lasting a few hours.

Fluid

Athletes must remember to replace their fluids or they will get dehydrated. This goes for winter as well as summer. The water loss, however, may cause problems for the runner. During a marathon, runners typically lose between one and 5% of their body weight even when the temperature is not high and regular drinks are taken throughout the event. In hot weather, as much as 8% of the body weight may be lost. Weight loss is almost entirely due to water loss, and reductions in the plasma volume and cellular water content result. Remember adequate fluid intake will help to guard against dehydration. Thirst is not a reliable guide to the need to drink. Take fluid before you feel thirsty.

Which of these is best?

This question is not easy to answer. Fluid intake is aimed not only at the replacement of water and electrolyte losses, but also at the provision of fuel, normally glucose, for the working muscles. It is important therefore, that the athlete starts the race or training well-hydrated. Working out which of the fluids is best is a matter of trial and error. It is important therefore for the athlete to avoid alcohol and coffee as these are powerful diuretics and may leave you dehydrated. Colder solutions empty from the stomach more rapidly than warm solution. Do not worry about chilling your stomach despite the popular theory, stomach cramps are more likely to be the result of an overstrong solution sitting in your stomach.

Conclusions

1. A well balanced diet will allow you to train and perform at your best
2. Spread the daily intake of food over three regularly spaced meals
3. Every day include fresh vegetables and fruit in the diet
4. Curb the ingestion of fatty foods
5. Exclude from the diet as much as possible foods that furnish calories only without contributing their share of vitamins i.e. sweets, chocolate, cakes and pop drinks, coke etc., and substitute fruit and fresh fruit drinks for snacks
6. Decrease or curtail the intake of tea, coffee and alcohol for these drinks take the place of more nutritional food stuffs and may cause undesirable biochemical effects such as a decrease in muscular efficiency. Drink more fruit drinks, water and even milk (milk is one of the best all round sources of nutrition)
7. Alcohol in moderation is not harmful to the athlete but remember its dehydrating effects which may impair performance
8. Athletes should be aware of their feeding habits and composition of their food especially with regard to days of intensive training and competition

About this article

The information on this page is adapted from an article "Diet/Proper Nutrition" written by Cliff Gould which was first published in "Athletics Coach", March 1990. (Athletics Coach ceased publication in 1997)

Associated Pages

The following Sports Coach pages should be read in conjunction with this page:

• Coaching Articles
• Training Articles
• Sports Specific Articles
• Literature Review