Amino acids

Amino acids and proteins

From a chemical point of view, proteins are one of the most structurally and functionally complex molecules. Just think, the structure and chemistry of each protein has been developed and refined over billions of years of evolutionary history. There are 20 types of amino acids in proteins, each with different chemical properties. A protein molecule consists of a long chain of these amino acids, each of which is linked to its neighbor by a covalent peptide bond. Proteins are therefore also known as polypeptides. Each type of protein has a unique amino acid sequence, exactly the same in every molecule. Many thousands of different proteins are known, each with its own amino acid sequence. This is enough to make us realize how important amino acids are.

What are amino acids?

Both animal and plant proteins are made up of around 20 common amino acids. The proportion of these amino acids varies depending on the properties of the protein, but all food proteins - with the exception of gelatin - contain a portion of each. Amino acids are essential for the synthesis of body proteins and other important nitrogen-containing compounds such as creatine, peptide hormones and some neurotransmitters. Proteins perform a variety of functions in the body, including DNA replication, transporting molecules, catalyzing metabolic reactions, and providing structural support to cells. Although we define the need for protein, the actual biological requirement is amino acids.

Are Amino Acids Necessary?

Yes! And so on and on throughout our lives. Proteins and other nitrogenous compounds are constantly degraded and re-synthesised. Several times more protein is converted in the body each day than is normally consumed, indicating that amino acid reuse is a major feature of the economics of protein metabolism. This recovery process is not entirely efficient, and some amino acids are lost through oxidative catabolism. Amino acid metabolic products (urea, creatinine, uric acid and other nitrogenous products) are excreted in the urine; nitrogen is also lost in feces, sweat and other bodily secretions, and in shed skin, hair and nails. To replenish these losses, it is necessary to constantly supply amino acids in our diet, even after the age when we are growing intensively.

Essential amino acids and non-essential amino acids

There are several criteria for the division of amino acids. We will focus here on the most popular split that you have surely heard of. We distinguish:

1. Amino acids that the body is unable to synthesize itself or the rate of synthesis does not adequately meet the body's needs and must be taken with food - they are referred to as exogenous or essential amino acids;
2. The amino acids that our body is able to synthesize are referred to as endogenous or non-essential amino acids (they are produced from other amino acids, or from carbohydrate and fat metabolism products).

What are EAAs?

Nine amino acids are considered essential amino acids (EAAs). They are essential for new protein structures and cannot be produced by the body in physiologically significant amounts, so they must be supplied as key components of a balanced diet. EAAs include histidine, isoleucine, leucine, valine, lysine, threonine, phenylalanine, methionine, and tryptophan. Three of the nine EAAs (leucine, valine and isoleucine) are branched-chain amino acids (BCAAs). The remaining 11 amino acids are conditionally essential and endogenous amino acids, which include: glycine, alanine, arginine, asparagine, aspartic acid, glutamine, glutamic acid, proline, serine and tyrosine, cysteine.

What is BCAAs? Do BCAAs work?

Branched Chain Amino Acids (BCAAs), i.e. leucine, isoleucine and valine, are three of the nine essential amino acids (EAA). Leucine is not only a precursor of muscle protein synthesis, but can also play the role of a regulator of intracellular signaling pathways that are involved in the process of protein synthesis. BCAAs stand out among the essential amino acids in that they are not metabolized in the liver, but in skeletal muscles. The concept that branched chain amino acids may have a unique ability to stimulate muscle protein synthesis was presented about 40 years ago. Did you know that research results are still ambiguous and the discussion whether BCAAs actually work is still going on? It has been suggested years ago that BCAA supplementation may reduce protein degradation and/or muscle enzyme release, reduce skeletal muscle damage in response to intense resistance exercise, alleviate central fatigue, and promote subsequent recovery of muscle function. Research is still ongoing. However, given all the physiological mechanisms associated with BCAA use and the fact that they are mainly metabolized in skeletal muscle while other essential amino acids are catabolized in the liver, BCAA supplementation has been identified as a potential nutritional strategy.

Arginine and citrulline, i.e. amino acids associated with the muscle pump

Nitric oxide plays an important role in our body. It is known to dilate blood vessels, improving circulation and improving the efficiency of the mitochondria. It performs a number of physiological functions [e.g. increases muscle contractility, improves exercise tolerance and regulates oxygen consumption]. L-arginine is a precursor from which nitric oxide is synthesized in endothelial cells. Increasing the amount of L-arginine in the circulation may be a potential mechanism to increase nitric oxide synthesis and bioavailability. It turns out, however, that L-citrulline has the ability to increase the availability of L-arginine for the production of nitric oxide. So what does citrulline give us? Citrulline supplementation is believed to be as effective, if not more, than arginine supplementation alone in increasing nitric oxide production.

What about AAKG?

As mentioned above, the amount of L-arginine in the body can be the rate-limiting step in nitric oxide production. Recently, dietary supplements in which L-arginine is combined with alpha-ketoglutarate (AAKG) are becoming more and more popular. Alpha-ketoglutarate is a compound that plays an important role in metabolism and is involved in many biochemical reactions, including energy production and amino acid synthesis. This compound is often found in dietary supplements, especially in combination with L-arginine. Exogenous supply of alpha-ketoglutarate through a supplement such as L-arginine alpha-ketoglutarate (AAKG) can increase the flow of the Krebs cycle. Alpha-ketoglutarate may have a glutamate-sparing effect in the body. This is important because alpha-ketoglutarate can be replenished through the transamination (appropriate chemical reaction) of glutamate, which is an amino acid necessary for protein anabolism; also known as a very important neurotransmitter that stimulates the nervous system.

What is glutamine?

CAn interesting fact is that of the 20 amino acids listed in the genetic code, glutamine is the best example of the versatility of amino acid metabolism. Glutamine is the most abundant and multidirectional amino acid in the body and is fundamental to various biological functions, such as cell proliferation, energy production, glycogenesis, ammonia buffering, acid-base balance maintenance. In almost every cell, glutamine can be used as a substrate, e.g. for the synthesis of nucleotides (purines, pyrimidines and amino sugars), antioxidants and many other biosynthetic pathways involved in maintaining cell integrity and function. Glutamine is a conditionally essential amino acid widely used in the nutrition of physically active people and professional athletes.

Let's not forget about beta-alanine

Beta-alanine is one of the most widely used sports supplements in the world. It increases intracellular buffering capacity with potentially beneficial effects on sustained high-intensity exercise performance. Interestingly, it has limited ergogenic properties by itself; however, beta-alanine has been identified as the rate-limiting precursor to carnosine synthesis and has been consistently shown to increase carnosine levels in human skeletal muscle. The basic role of carnosine in the metabolism of skeletal muscles is to act as an intracellular buffer - this means that it affects the maintenance of optimal pH. And how does it work? Well, during high-intensity exercise, due to the dominant energy system (anaerobic metabolism of carbohydrates), there is a high release of hydrogen protons (H+), which leads to a decrease in pH. This drop in pH can negatively affect the metabolic processes that contribute to the onset of muscle fatigue. Carnosine is found in muscle tissue and acts as a hydrogen proton buffer in short-term, high-intensity exercise. It's an immediate defense against the accumulation of protons in contracting muscles during exercise.

Amino acids from 6PAK Nutrition

If you still don't know which amino acids to choose from our offer - here's a short cheat sheet :)

• EAA - i.e. a set of essential exogenous amino acids is an ideal pre-workout product. Remember how important amino acids are for the human body, especially for the body that leads an active lifestyle and intense workouts. EAA also includes in its composition BCAA, i.e. branched chain amino acids in the optimal ratio of 2: 1: 1. You don't know which amino acid product to choose? EAA will be a hit!
• BCAA - branched chain amino acids (i.e. L-leucine, L-isoleucine and L-valine) in the optimal 2: 1: 1 ratio. The product has been additionally enriched with vitamin C and two B vitamins: B6 and B12. If you are going to train - BCAAs will always be a good choice. The instant form of amino acids guarantees excellent solubility. BCAA from 6PAK will definitely not disappoint you!
• Anticatabolic - it is also a product in which you will find BCAA amino acids in a 2: 1: 1 ratio. But it is not everything! The composition also includes L-glutamine and taurine and the addition of vitamins: C and B6. A great proposition for a training day - you drink half a portion before training, and the rest during training. Perfectly developed formula - you will be satisfied! Anticatabolic does the job!
• Glutamine - that is, in fact, a combination of three active ingredients: L-glutamine, taurine and vitamin B6 in perfectly matched proportions. It is a product to be used before and after training. If you don't know which pre-workout formula to choose - try Glutamine. It should also be mentioned here that it is a powdered product in a flavorless version, but the composition is based only on 3 ingredients - you will not find any additional substances here.
• Beta-alanine - beta-alanine in the form of powder with the addition of vitamin B6. This product is designed for people with increased physical activity. One serving is 800 mg of beta-alanine - it is recommended to use up to 3 such servings a day. But don't worry, the packaging is efficient - it provides a total of 248 servings! With Beta-alanine, no workout will be too hard!
• Citrulline - citrulline malate in powder form. A tiny scoop (only 3 g) can take your training to another level. Citrulline is perfect as a pre-workout. It is a product with one active ingredient, but it may surprise you. Bet on Citrulline!
• AAKG - in our offer you will find L-arginine alpha-ketoglutarate in the form of powder and in the form of tablets, which is something good for everyone. In addition, the powder option has been additionally enriched with taurine and vitamin B6. Just find a place for AAKG (powder or tablets - whatever you prefer) in your training plan and enjoy the results of your hard work.

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