Biological background
BCAA is a combination of different amino acids. It can be administered in the form of dietary supplements, but the basic need for these organic compounds can also be met naturally.
What are amino acids, and what function do they perform in the human body? Essential amino acids cannot be produced by the human organism itself, so they must be supplied through dietary intake. As building blocks that are assembled to form proteins, they perform important functions in the organism. This is because proteins are the most important building blocks of life.
Amino acids are the basic building blocks of protein compounds. When they fulfill this function, they are called proteinogenic amino acids, of which 23 naturally occurring ones are known to date. But in addition, numerous other biological functions are known to be performed by this class of organic compounds. Science currently knows about 400 non-proteinogenic amino acids that occur in natural biomass. However, since amino acids can also be produced synthetically, their actual total number is difficult to estimate.
Chemically, amino acids are carboxylic groups that are also characterized by a nitrogen-containing amino group.
BCAA is the abbreviation for “branched chain amino acids”. The most important representatives of this group are the three compounds isoleucine, leucine and valine , which are particularly important for athletes because they are associated with the thickness growth of body muscles. And this is then the content area in which BCAAs receive special attention: professional sports. But what do amino acids basically have to do with muscle building and competitive sports?
Like all animal organs, muscles are made up of cells, but they have certain special features. They are so-called syncytia, i.e. multinucleated cell bodies that have developed from several individual cells. Unlike normal somatic cells, they have lost the cell membranes that normally separate the cytoplasm (the inner space of a cell with cell organelles) from that of the neighboring cell. In this case, muscle growth in the sense of cell proliferation is not possible. The muscle cells, which correspond to the individual muscle fibers, can only achieve the size of their cross-section by storing more protein. The incorporation of new protein molecules is the ultimate consequence of stimulation of the muscle cells. This is based on a stimulus in the form of a microscopic cell injury, the intensity of which must exceed a tolerated threshold. A cascade of biochemical reactions finally leads to protein biosynthesis, the mass increase of the body muscles. The two branched-chain amino acids leucine and isoleucine are particularly involved in this process. Leucine supports the build-up of muscle tissue and the formation of important proteins in the liver. Isoleucine is part of a reaction chain that supplies the muscle fibers with the necessary energy. Valine is a component of important enzymes and also supports the energy supply of the muscles. It is also a component of protein biosynthesis, especially within muscle cells. Leucine, isoleucine and valine are therefore important amino acids, with which especially strength athletes must be supplied in sufficient quantities.
In general, the BCAAs correspond to about 50% of all essential amino acids consumed through food. Leucine, isoleucine and valine are known from various natural foods. For example, valine was first obtained from cow’s milk, which incidentally has the highest proportion of this amino acid compared to other nutrient sources. However, valine is also a component of various fruits such as wheat, rice , peas or walnuts. But also the consumption of salmon, beef or chicken meat is able to meet the human need for valine.
Leucine is also an essential amino acid found in numerous natural resources. It often occurs together with its constitution isomer isoleucine. Both of them are often components of foods that also contain valine. Therefore, cow’s milk again proves to be a particularly rich source of both isomers. Otherwise, the nutrient-rich fruits of wheat, peas or rice provide rich sources of those three amino acids, which fulfill important functions in connection with muscle building. Leucine not only supports the synthesis of muscle protein for storage in the muscle fibers, but also prevents the breakdown of muscle substance in situations of physical exertion. It also promotes healing processes in case of injuries.
As already mentioned, isoleucine serves, among other things, as a component of muscle proteins. However, it is also an important supplier of energy, which can be available in particular at times when the body is supplied with fewer nutrients, for example in connection with a diet. Here, isoleucine interacts efficiently with leucine so that athletes do not lose muscle mass during their diets. Normally, the body reacts to a persistent nutrient deficiency first by converting energy stores (body fat) into energy-rich compounds, but then also by breaking down the muscles, whose proteins are thereby also supplied for energy production. The regular intake of BCAAs, either through natural food components or in the form of purchased supplements, prevents the undesirable loss of muscle mass even when the energy supply is reduced.
While isoleucine also stimulates the production of insulin in the pancreas, valine regulates blood sugar levels by stimulating the release of insulin. Leucine contributes to the formation of glycose (energy-rich sugar) and thus supports the energy balance of the body, especially the muscles. All three nutritional components are thus firmly linked in a complex way to the formation and long-term maintenance of muscle mass. Especially in connection with diets, the natural supply of amino acids is more difficult, which is why it is often recommended to administer them in the form of dietary supplements.
Biologically, it is not easy to distinguish between essential and non-essential amino acids. This is due to the fact that there are representatives that only need to be supplied to the body from the outside at certain times of individual development, such as arginine and histidine. In the case of metabolic diseases, it can also happen that those amino acids become essential which the body is able to produce itself under healthy conditions. Others can be secreted by the human organism itself, chemically modifying essential amino acids.
Essential amino acids, which include BCAAs, are produced by plants and enter the food chain through our animal foods, such as beef or fish. In fact, plants possess properties that we lack: they can produce energy-rich organic compounds themselves from light energy in the presence of water and carbon dioxide. This is why they are also called autotrophic organisms, to be contrasted with the heterotrophic animals, which have to absorb important nutrients from outside.
Food supplements
The amount of essential amino acids that a normal healthy adult should have can be easily provided by the natural resources mentioned in the previous chapter. In this regard, approximately 10 to 50 grams of BCAAs should be consumed daily with food.
It is not surprising, however, that this amount must be increased several times over if a competitive sport is practiced. Although a distinction must be made between endurance and strength sports, both have in common that a correspondingly greater nutrient requirement is built up through increased physical stress.
For reasons of performance and due to aesthetic expectations of an athletic body, professional athletes must control their diet very closely. Excessive cholesterol-rich diets must be avoided, as too much storage fat has a negative effect on metabolic performance. Since regular diets must be followed to ensure a purification of the body and, above all, to be able to maintain an optimal body weight, the organism is naturally faced with an existential problem: lack of food should not lead to a breakdown of muscle protein. Therefore, proteins and other energy-rich compounds must be available to the body as far as possible, but at the same time as little sugar and fat as possible should be supplied. Therefore, exclusively natural foods quickly become inefficient. Targeted supplementary nutrition is now required, for example in the form of special BCAA preparations.
BCAA can be ingested in various dosage forms. Powder or capsules are to be preferred to tablets if a quick effect is to be achieved. This is because the digestion of tablets to release the amino acids takes a longer time window.
However, athletes must also consider the right time to take the supplement if the nutrient addition is to be as efficient as possible. Experts therefore advise that the supplementary food should only be administered after training has been completed, as larger amounts of insulin are released at this time. This proteohormone, which primarily serves to make energy-rich sugar available to the cells, also serves to accelerate the supply of essential amino acids to the muscle cells.
An athlete should consume up to a maximum of 20 grams of BCAAs daily in the form of dietary supplements, preferably in a ratio of two parts leucine and one part each isoleucine and valine.
Amino acids represent a class of organic compounds in chemistry. They each contain at least one carboxy group and one amino group. This makes them part of the group of carboxylic acids as well as a member of the group of amines. In simple terms, amino acids are carboxylic acids that have an amino group instead of a hydrogen atom. Amino acids are divided into different groups. The position of the amino group in relation to the carboxyl group is decisive for determining which amino acid belongs to which group. Carbamic acid is the simplest of all amino acids. It has only one carboxyl and amino group. The carbon antom, to which the amino group is attached, provides information about which class of amino acid it is. If there is more than one amino group, the carbon closest to the carboxyl group is decisive.
This results, for example, in the alpha-amino acids. The amino group is located at the second carbon atom, and counting starts at the carboxyl carbon. For beta-amino acids, the amino group is located at the second carbon atom, and for gamma-amino acids, it is located at the third. In this way, the different classes can be continued. The IUPAC nomenclature is also similar. Alpha-amino acids are called 2-aminocarboxylic acids because their amino group is connected to the second carbon atom. Accordingly, beta-amino acids are called 3-aminocarboxylic acid and gama-amino acids are called 4-aminocarboxylic acid. The scheme thus remains the same and can be continued both for classification into classes and for nomenclature.
Almost all amino acids have a chrial structure. The only exception is glycine. Chirality is a special arrangement of the molecular groups, which results in different forms. The decisive factor here is the arrangement around the asymmetric carbon atom. This also explains the non-chiral structure of glycine, which does not have an asymmetric carbon atom. A distinction is made between L-amino acids and D-amino acids. The chemical behavior of L- and D-amino acids is homogeneous, the difference is mainly based on the present form. Only L-amino acids are used for protein synthesis. The forms are referred to as stereoisomers.
Further differences are found for amino acids within the groups. The respective amino acid as well as its property is determined by its side chain. This is also called “amino acid residue”. A side chain is a chain of carbon that comes off another, longer carbon chain and is crucial for the structure of the molecule. This residue replaces a hydrogen atom and gives the amino acid its characteristic individuality. For example, an alkyl substituent may be incorporated into the side chains, but hydroxy, amino, or the addition of carboxy groups is also possible. In general, side chains are differentiated into polar and nonpolar ones. Non-polar amino acid chains have hydrophobic properties. Hydrophobic is understood to mean “water-repellent.” Polar amino acid chains, on the other hand, are hydrophilic. Whether an amino acid is polar or nonpolar is determined by the amino acid residue.
This results in 20 different amino acids in the human body that make up proteins. These are also called “proteinogenic” amino acids and are irreplaceable. In addition to these proteinogenic amino acids, there are many more. However, all other amino acids are irrelevant for protein synthesis. Proteinogenic amino acids are in the L-form and are always alpha-aminocarboxylic acids. They therefore belong to the alpha class.
Amino acids can be essential, non-essential or semi-essential. While non-essential amino acids are produced by the body itself, essential amino acids must be obtained externally, for example through food intake. Semi-essential amino acids are amino acids that can be formed from other amino acids. For example, methionine can synthesize cysteine. This is especially important in certain situations. One example is the increased need for protein, as is the case during the growth phase. Arginine, asparagine, cysteine, glutamine, glycine, proline, tyrosine are semi-essential. When certain conditions are met, they become essential.
Essential amino acids are L-isoleucine, L-leucine, L-lysine, L-methionine, L-phenylalanine, L-threonine, L-typtophan as well as L-valine. L-alanine, L-arginine, L-aspartic acid, L-asparagine, L-cysteine, L-glutamine, L-glutamic acid, L-glycine, L-histidine, L-proline and L-serine, on the other hand, are non-essential.
The different amino acids also have differentiated roles in the human body. Isoleucine, for example, is crucial for muscle building, which is why it is often found in preparations for athletes. In natural foods, they are found in the form of cashews, peanuts and lentils.
Valid keeps blood sugar within a healthy range and can be consumed through yeast, oatmeal and spelt flour. Methionine directly helps in the production of protein. It also contributes to muscle building and can be found in Brazil nuts, among other foods. Tryptophan is crucial for the production of serotonin as well as melatonin, through which it indirectly intervenes in the well-being of humans. Melatonin is especially necessary for sleep. Tomatoes, carrots, bananas and spinach contain the important amino acid. Lysine is needed for the maintenance of muscles and connective tissue. It is found in beans, oranges or celery. The body can also produce carnitine from lysine. White and red blood cells are irreplaceable in the human body. Phenylalin is crucial for the production of these. It is found in pumpkin seeds and soy. Threonine has two functions. First, it can be converted into glycine, and second, it helps the body form bones as well as maintain the immune system. This is done through the production of antibodies. Papaya, carrots and leaf spinach ensure an optimal supply of the amino acid.
Arginine and tyrosine are semi-essential. They are not yet present in the body of an infant and can only be produced by the infant itself as it grows. Until then, it must be supplemented externally. Arginine supports the development of muscles and growth in general, while tyrosine is used to produce hormones for the thyroid gland.
The production or intake of amino acids is therefore necessary for survival. In healthy people, supplementation of the substances by capsules, tablets or other drugs is not necessary. Normally, all amino acids are absorbed in sufficient quantities through food. An increased protein intake can then be rather detrimental to health. According to the German Society for Nutrition, the consumption of 0.8 grams of protein per kilo of body weight is sufficient. Only in cases of serious illness, surgery or the presence of malnutrition can it be useful to supplement amino acids. People who regularly train very intensively and are designed to build up muscles also have an increased need for amino acids. Here, special attention should be paid to a healthy diet. Otherwise, good quality supplements in the form of capsules etc. are recommended. If an additional supply is necessary, those affected should seek professional help. Most over-the-counter dietary supplements often contain only small doses of amino acids, which are already covered by small amounts of certain foods.
Vegetable products such as legumes, nuts, spinach, pasta and potatoes contain sufficient protein so that even vegetarians and vegans are not in danger of showing deficiency symptoms. In Germany, a deficiency of amino acids is therefore rather rare, so that the intake of tablets and capsules can be dispensed with.
