Food components
The food is made up of the following ingredients:
Carbohydrates
Carbohydrates are the fuel of the cells and are therefore particularly important for providing energy during hard physical work or sporting activity. Carbohydrates are therefore the most important sources of energy in terms of quantity. Around 50 per cent of our daily energy intake should come from carbohydrates.
The basic requirement is 140g per day, because the brain and red blood cells need approximately this amount to function. However, the body also stores carbohydrates in the form of glycogen in the muscles and liver. These reserves are then used up during increased physical exertion. In order to maintain performance in the long term, these stores must be constantly replenished. Exhausted glycogen stores require 24 hours for complete regeneration. If this regeneration time is not adhered to, this can lead to a drop in performance.
Basic foods such as pasta, rice or potatoes are suitable for carbohydrate intake. For active athletes, it is recommended to consume 4-8g of carbohydrates per day and per kilogramme of body weight. For less active people, the recommendation is 3g. With moderate exercise, we are talking about 300g for men and 240g for women (mainly in the form of polysaccharides/starch).
The glycaemic index (GI) must be taken into account when planning your diet. Foods with a high GI value should be consumed during or after exercise and those with a low GI value during periods of physical inactivity. The GI indicates how long digestion takes and how much the blood sugar level rises. If a lot of energy is needed quickly, foods with a high GI must be consumed.
Fat
Fat is the most important source of energy during low-intensity and long-duration exercise and is the largest energy store in the body. There are three groups of fatty acids: saturated, monounsaturated and polyunsaturated fatty acids. Fat is a flavour carrier and also contains vitamins A, D, E and K.
Monounsaturated and polyunsaturated fatty acids are important for long-term good health. Adequate fat intake is particularly essential in sports nutrition, as it is often the case with active athletes that their fat intake is too low, which can lead to long-term health problems. Fat intake can be provided by high-quality oils, nuts or fish, for example.
The recommendation for daily fat intake for active people is 1.5-2g per kilogramme of body weight and should correspond to around 30-35% of total energy intake. For less active people, the recommended daily value is 1g per kilogramme of body weight. To ensure a good balance of fatty acids, all three forms of fatty acids should be consumed in roughly equal amounts (1/3 distribution).
Protein
Plant or animal proteins ingested with food are converted into the body's own proteins. Proteins make up hormones, enzymes, genetic information and many other components of our body. Proteins are the basic building blocks of our muscles and other cells, such as skin and hair. Proteins are required by the body to enable all processes associated with muscle work to run effectively.
Proteins are not only relevant for weight training, but athletes generally have an increased protein requirement. The recommended amounts are between 1.2-1.8g per kilogramme of body weight per day for athletes and 0.8g per kilogramme of body weight per day for less active people. Protein-rich foods are mainly meat, fish, eggs, dairy products, beans, peas, lentils and soya.
Vitamins
Vitamins are needed to perform and maintain a wide range of physiological functions. They cannot be (sufficiently) produced in the metabolism and must therefore be taken in with food. We distinguish between fat-soluble (A, D, E and K à body reserve) and water-soluble (B and C à no body reserve) vitamins. Every food naturally contains a spectrum of vitamins. The fresher the food, the higher the vitamin content.
Each of the 13 vitamins has its own, irreplaceable function. If the diet is varied, the vitamin requirement can usually be met; only if the diet is unbalanced should vitamin supplements be considered.
Minerals
Minerals are naturally occurring inorganic elements. Most minerals are found in the soil, where they are absorbed by plants and animals and thus reach humans through food (plant and animal foods).
Minerals take on the role of building materials (e.g. in bones, teeth and muscles), but are also regulatory substances, mostly as components of enzymes. The body has precise control systems to regulate the absorption and excretion of minerals. The minerals excreted through sweat, urine and faeces must be constantly replaced through food. Essential minerals are: sodium (Na), potassium (K), chloride (Cl), calcium (Ca), phosphorus (P), magnesium (Mg), iron (Fe), copper (Cu), zinc (Zn), chromium (Cr), selenium (Se).
Nutritional fibres
Dietary fibre has a filling effect, prevents constipation and lowers blood cholesterol and blood sugar levels. However, foods rich in dietary fibre are difficult to digest and should therefore be avoided before and after intense physical activity. On the one hand, because this prolongs the emptying of the digestive tract and, on the other hand, because the digestion of dietary fibres delays the absorption of carbohydrates.
Dietary fibre is found in unrefined cereals, pulses, potatoes, vegetables and fruit. A minimum of 30g per day is recommended.
Secondary plant substances
Secondary plant substances support the immune system, have an anti-inflammatory effect or prevent cancer and cardiovascular diseases. These substances are contained in vegetables, fruit or cereal products in the form of flavourings, colourings or protective substances. A diet with a variety of flavours and colours is therefore very sensible, as each flavouring or colouring agent fulfils a different function in the body.
Water
A balanced fluid intake should be aimed for throughout the day. People need 2-3 litres of fluid per day. Half of this requirement should be covered by drinks (approx. 1-2 litres of water) and the other half by solid food. During exercise, the body loses about 1 litre of sweat per hour. This loss of fluid must be compensated for, so an additional 1.5 litres of fluid must be consumed per hour. If the body is supplied with too little fluid, it cannot cover the loss, as a certain amount of fluid is still excreted via the kidneys as urine.
Checking the urine is a simple method of monitoring the fluid balance. Light-coloured urine is a sign that the water balance is in order. Dark, strong-smelling urine, on the other hand, is a sign of dehydration or possible metabolic disorders in the body.