Branched-Chain Amino Acids (BCAAs) relate to three of the most important amino acids, namely:

• isoleucine
• leucine
• valine

However, BCAAs are probably one of the most misunderstood sports supplements on the market. This comes down to the various ways the products have been marketed which has caused confusion with some of the genuine science behind them. So, let’s start at the beginning.

What are amino acids?

Put simply amino acids are the building blocks of protein and therefore human bodies rely upon amino acids. These amino acids are responsible for everything from protein synthesis to collagen production and the effective use of calcium within the body. Some are even responsible for the maintenance of our neural-network, connecting our nerves and muscle to our brain. Without amino acids, not only could your body not grow and develop, it would not be able to repair itself or perform the critical functions it needs to survive.

Until recently it was believed that there were 20 amino acids that create protein (proteinogenic), however, studies have shown that there are two more, making a total of 22 amino acids:

1. arginine
2. alanine
3. asparagine
4. aspartate/aspartic acid
5. cysteine
6. glutamate/glutamic acid
7. glutamine
8. glycine
9. proline
10. serine
11. tyrosine
12. selenocysteine
13. pyrrolysine
14. histidine
15. isoleucine
16. leucine
17. lysine
18. methionine
19. phenylalanine
20. threonine
21. tryptophan
22. valine

These 22 amino acids are broken down into three categories:

• Essential
• Non-essential
• Semi/conditionally essential

The 9 essential amino acids

The essential amino acids are:

• Histidine
• Isoleucine
• Leucine
• Lysine
• Methionine
• Phenylalanine
• Threonine
• Tryptophan
• Valine

Essential amino acids are those that the human body cannot create on its own. These essential amino acids must therefore be obtained through your nutrition. Thus, it is essential that your diet contains enough of these essential amino acids to meet your body’s requirements. If you are an athlete, a very active person, a regular gym goer who trains hard or someone looking to build lean muscle mass, you are going to require more of these essential amino acids than the average person. So, when we say essential, we mean it.

The 13 non-essential/semi-essential amino acids

1. arginine
2. alanine
3. asparagine
4. aspartate/aspartic acid
5. cysteine
6. glutamate/glutamic acid
7. glutamine
8. glycine
9. proline
10. pyrrolysine
11. serine
12. tyrosine
13. selenocysteine

The 13 mon-essential/semi-essential amino acids listed here are classed as such because the human body is capable of producing these by itself (with the exception of pyrrolysine, which humans do not use), although this is not the whole picture because there are circumstances where the body might need more of these amino acids than it is capable of producing. Primarily these circumstances arise when the body is under stress, such as during an illness.

The Importance of Branched-Chain Amino Acids (BCAAs)

Within the nine essential amino acids, three have been highlighted in studies as those most responsible for the growth of muscle tissue as well as the retention of muscle when the body is under a catabolic state. These are Leucine, Isoleucine and Valine. This is the combination you will most commonly find in BCAA products aimed at bodybuilders and athletes. If we isolate these 3 amino acids, then their main combined function is twofold:

• Promote protein synthesis and the growth of new muscle cells (muscle growth)
• Provide anti-catabolic protection for existing muscle when dieting (on a calorie deficit)

These are two very powerful functions when you consider the main aim for the bulk of modern-day gym goers and athletes is to gain lean muscle while minimising fat stores. That said, it’s also important to remember that these are not a miracle product. You can get your average requirement of daily BCAA intake from regular foods without needing BCAA supplements at all. This is a tricky road though and is not as simple as it sounds - particularly if you are following a vegan diet. While many vegan foods are rich in amino acids, it is considerably easier to obtain the required amount on an omnivore diet which includes meat, fish and dairy. This is particularly the case when it comes to getting enough of the three main muscle building essential amino acids we have just outlined.

While protein sources like soy beans, peanuts, pumpkin seeds and other beans do have strong amino acid profiles for the vegan athlete or bodybuilder, you’d need to consume enormous amounts of these foods in order to match the essential amino acid intake needed to grow and maintain muscle. This is where the production of vegan BCAA supplements, particularly those high in Leucine, can be a huge advantage for the modern-day vegan athlete.

Benefits of Branched-Chain Amino Acids (BCAAs)

As we have discussed above, BCAAs have been shown in scientific studies, to provide a number of benefits, in particular:

• leucine helps to stimulate protein synthesis, reduce protein breakdown and can be a useful source of energy, even more superior to glucose
• isoleucine helps to support the immune system and metabolising muscles
• valine helps to maintain mental alertness, muscle coordination and can help with managing mental stresses.

Amino acids - recommended daily intake

The World Health Organisation recommends the following daily intake of essential amino acids per 1kg of bodyweight:

• Valine: 26mg per kg
• Tyrptophan: 4mg per kg
• Threonine: 15mg per kg
• Phenylalanine (and Tyrosine*): 25mg per kg
• Methionine (and Cysteine*): 15mg per kg
• Lysine: 30mg per kg
• Leucine: 39mg per kg
• Isoleucine: 29mg per kg
• Histidine: 10mg per kg

* non-essential amino acids recommended.