Proteins are macro-molecules that are composed of amino acids. Amino acids may be declared on package labeling, although they are expressed as protein, or rather in their configuration as a long chain. A product advertised in this way is therefore not an amino acid product, but rather a protein product. This can be tested upon dissolving the product (for example in water) – a large concentration of protein in water results in heavy clumps, like yogurt. The body cannot immediately assimilate the energy from these protein products. They must first be broken down in the digestive tract.

Proteins are our body’s building blocks, and they are responsible for a multitude of functions as structural proteins, enzymes, transport proteins and much more. By quantity, by far the most protein in our body is stored in the bones, skin, sinews and cartilage. The muscle protein, myosin, together with actin, forms the actin-myosin complex. By shortening the filaments of the acto-myosin, it causes muscle contraction and thereby makes movement possible.

The muscles are largely comprised of protein, which are composed of nitrogen, carbon, hydrogen, oxygen and sulfur. Because all of the body’s organs undergo a continuous construction and deconstruction, protein is constantly required. In the deconstruction of the protein structures, a large portion is recovered and reused. However, because the organism cannot store large quantities of protein, we must assume it on a daily basis through our nutrition. The proteins we take in must first be converted into amino acids in our digestive tract – they must be broken down into their building blocks in order for the body to assimilate them. Through the process of metabolism the amino acids arrive in our cells. Some 70% of the free amino acids are found in the skeletal musculature.

Another portion of the amino acids is used for the catabolic exchange, or for the composition of nitrogen containing compounds such as creatine or purine bases.

Modern medicine has discovered over 250 amino acids with various functions. For complete nutrition and sports nutrition, the most important group is that of protein-building amino acids. On its own, the human body cannot produce eight of these altogether 22 amino acids. These essential amino acids must be obtained through nutrition. In the meantime, we have also discovered a number of semi-essential amino acids, which must be obtained regularly, that play important roles in our metabolism.

According to present knowledge and research in sports medicine, this subdivision of essential and non-essential amino acids is, in retrospect, no longer sensible. It has been shown that under various living conditions and athletic strain there can be some shifting between the essential and non-essential amino acids. For example, in strength training, there is a greater need for non-essential muscle building amino acids; in certain cases they can be utterly necessary for survival and therefore, essential.

Among the essential amino acids, the so-called BCAAs play a special role. BCAA is an acronym for “branched chain amino acid”. These double-chained amino acids are a mixture of leucin, isoleucine and valine. These amino acids are considered essential, that is, the body cannot produce them by itself and they play an important role in muscular catabolism. While most essential amino acids are absorbed through the small intestine and metabolized in the liver, the bulk of the BCAAs are directly absorbed by muscle, serving there to provide nitrogen (NO) for the formation of autochthonous proteins.
With the specific administration of BCAAs in a scientific study, muscular injuries could be significantly reduced. The serum concentration of the muscle enzymes CK and LDH, which function as indicators of a muscle injury due to strain, increased in all subjects in the hours and days following the strain, whereby the increase under BCAA supplementation turned out to be significantly lower.
Sources: Coombes JS, McNaughton LR: Effects of branched-chain amino acid supplementation on serum creatine kinase and lactate dehydrogenase after prolonged exercise. [Next page]