Neil Featherby's EDP Article.
A well balanced diet containing all the essential nutrients is a must for all those who take their running seriously. There are lots of fads and myths about foods, special diets and supplements which will allegedly improve performance, but just like training, if you haven’t got the basics correct then you will be under performing. For those who like to put a lot of effort into their training and running, a diet consisting of a high proportion (60%) of complex carbohydrates, 15/20% protein and 20/25% fat (essential fats) is one that best suits most athletes when it comes to ensuring that the food we eat not only meets our energy requirements, but also assists with recovery after training and racing.
For those taking part in marathons and long distance events, it is a good idea to increase the amount of carbohydrates in your diet for about three days beforehand. This doesn’t mean you eat more, but by increasing carbohydrates whilst reducing the fat and protein in your diet whilst also reducing your training loads will ensure that your glycogen levels are fully topped up when you stand on the start line. Glycogen storage will also increase water content as for every one gram of glycogen there will be three grams of water. This of course will produce a weight increase for which it is also best to try this out before race day so as to fully appreciate the benefits during the latter stages of marathons and other long distance events.
Carbohydrates are energy providing nutrients so as to provide the body with glycogen during exercise. Glycogen is stored in the muscles and liver. A high muscle glycogen concentration will allow you to train at your optimal intensity whereas a low muscle glycogen concentration will lead to fatigue and sub optimal performances. A well balanced diet containing all essential nutrients is a must for sports people with approximately 60% of the required calorific input coming from Carbohydrates. The highest proportion of these carbohydrates should come from foods that are low to medium on the Glycaemic food ranking list providing slow release energy.
*whilst some have preferred to reduce the amount of carbohydrates in their diet during more recent times, my own preferred personal choice for endurance athletes is still to maintain a high level of complex carbohydrates within the diet.
Glycaemic Index (G.I.)
The Glycaemic Index is a measure of the effects of different foods containing carbohydrates on blood sugar levels. If you need to get carbohydrates into your bloodstream and muscles cells quickly particularly after exercise then foods high on the GI will do this. However and in most cases it is the more slow released forms of carbohydrates which are best and are described as medium to low on the GI ranking of foods. Those that are high on the GI if eaten with fats and protein will also be more slowly released into the blood stream.
Protein is essential for muscle growth and repair and whilst it is very popular with many sports people to take protein powders and supplements the body only requires approximately 15% of the daily calorific requirement to be made up of protein. Proteins can be used for energy if the glycogen levels become low particularly during exercise which extends beyond 90 minutes of endurance training and competition. However, if muscle glycogen stores are high then less protein is broken down for energy whereby muscle repair and recovery after exercise is more rapid. Whereby it is very popular with some sports people to reduce the carbohydrate content in their diet for extra protein, the body only requires 1.4 gms to 1.8gms of protein per Kg of body weight and is more than sufficient enough for athletes. There are lots of powders and protein supplements on the market which are very popular, but as always the best source of essential nutrients comes from eating the correct foods within a balanced diet.
*For those who abstain from eating meat and fish, then eggs and dairy products are a good source of protein. However, for those who also prefer to follow a vegan diet, it is essential to cross mix an assortment of plant foods so as to obtain all nine essential (complete proteins) amino acids in the diet. Whilst it is thought that no plant food contains all the essential amino acids, this is not entirely true, but the amounts are indeed very small. For the vegan and vegetarian athlete who avoid dairy products, good sources of protein come from soy products and other beans/pulses, nuts and whole grains.
Fats should provide the body with about 25% of its energy requirements. Fats come from animal and vegetable sources. Whereas carbohydrates and proteins contain 4.1 kcals per gram, fats provide the body with 9.2 kcals per gram. Fats provide the body with several needs and if the recommended requirements are not met, then the body will not be able to function properly i.e. irregularities with hormone production, organ and cell protection, brain tissue, nerve sheaths, bone marrow and body temperature regulation as well as ensuring the absorption of the fat soluble Vitamins A, D, E & K. Fat also provides a huge supply of energy and whilst it can supply an efficient supply of fuel when combined with carbohydrate oxidation during exercise providing the runner is running at the correct pace (the quicker we run the more the body calls upon energy supplied from carbohydrates), once glycogen levels run low as in runners hitting the wall in marathons and long distance events, then fat oxidation becomes less efficient. Despite the importance of fats, it is also important to understand the difference between those which are considered as good fats and those that are known as bad fats so as to ensure that we consume the correct foods i.e. good fats monounsaturated and polyunsaturated as opposed to those that contain the bad fats trans and saturated.
Whilst the body can synthesize most of the required fats, linoleic acid (Omega 6) and alpha–linolenic acid (Omega 3) can only be obtained through eating specific foods within the diet and hence why these group of fatty acids are considered essential. Therefore, great attention should be paid towards ensuring that we consume the correct foods in respect of obtaining these good fats. However, and at the same time, it should also be pointed out that Omega 6 is far more easily obtained within a western diet for which the downside is that if we eat too many foods containing these fats, this can then inhibit the absorption of Omega 3 fatty acids. Good sources of Omega 3 and 6 fatty acids come from eating dark fish such as mackerel, sardines, pilchards, tuna, etc, nuts, seeds, oily fish, eggs, avocados, and olive and certain other vegetable oils. For vegetarians and particularly vegans, the Omega 3 fatty acids DHA and EPA are harder to obtain for which a vegetarian supplement (micro algae) may be worth considering.
Vitamins & Minerals
Whilst Vitamins and minerals do not directly provide the body with energy, without them the body would not be able to function properly. They all have differing roles, but combined they help with growth, energy metabolism, nerve function, vision, wound healing, maintaining healthy tissue, hormone production, red blood cells and oxygen transportation, cell protection, the immune system and to keep our bones strong.
Our bodies are made up of between 60 to 70% water for which all athletes should ensure that they take in enough water throughout the day to ensure that performance levels during training and competition are not impaired. The more energy expended the greater the requirement for fluid replacement. A loss of just 2% in bodyweight through fluid loss will reduce the body’s ability to function reducing performance levels greatly. Severe dehydration can needless to say result in far worse. Urine checks during the day should confirm your needs for water. If it’s clear or straw like in colour then fine, but if not then drink more until it is. About two hours prior to training consume 500 mls of water and consume 150 to 200 mls every 15 to 20 mins during exercise. Do not wait until you are thirsty! Drinks which contain 35 to 50gms of carbohydrate will help maintain carbohydrate oxidation. Those that contain electrolytes which are lost through sweat loss will also help.
Pre event/training meals
Pre event snacks/meals should be easily digestible containing carbohydrates so as to top up muscle glycogen stores and eaten about three hours before your workout or competition. This will allow enough time for your stomach to empty sufficiently and for blood sugar and insulin levels to stabilise. Liver glycogen will also be topped up. Include foods which are low on the G.I. for slow release energy, are low in fat, low in protein and not too bulky. Consume 500mls of water too.
If you are competing late in the day then try to eat sensibly throughout the day at approximately three hour intervals with your last meal 3 to 4 hours before your event. A very small snack about one hour before an endurance event will help to sustain energy and maintain blood sugar levels during the event. However always practice your dietary habits before training sessions as opposed to trying them out first time before competition.
Whilst many sportspeople take all sorts of potions in the hope that performance can be improved, a well-balanced diet should meet all essential requirements. However and with the pace of modern day life many sports nutritionists advise that taking a balanced multi vitamin with iron can help safeguard in the unlikely event of there being any small deficiencies. It is advisable to be aware that whist the water soluble vitamins in the B Group and Vit C will be excreted in the urine if taken in excess, the Fat Soluble vitamins A, D, E & K can become toxic if taken in excessive amounts as these will be stored in the body.
Energy and Electrolyte Drinks can help to not only maintain energy levels during long bouts of exercise, but will also help the body stay hydrated. However it is important to ensure that the concentration levels (mix) is at the correct levels. A 7.5 to 10%concentration is normally recommended i.e. 35/50gms per 500 mls of water or in hot temperatures 5% and below.
Recovery Drinks are okay particularly for those that train hard on several days throughout each week. They should predominately contain carbohydrates with a little protein so as to aid with energy replacement and muscle recovery.
The sports nutrition market is huge and whilst there are potions and pills available for just about everything, first and foremost, a well-balanced diet containing all the essential nutrients is far healthier and in most cases far tastier and more satisfying.