Amino acids are the "building blocks" of protein, and amino acid supplements are some of the most popular products on the market.

Despite their popularity, many consumers may not fully understand what purpose amino acids serve or the differences between one amino acid supplement and another one.

That's where this article comes in. We'll help discuss the most important amino acids as well as discuss the differences between EAAs and BCAAs, the two most common types of amino acid supplements on the market.

 

Two Types of Amino Acid Supplements: EAA or BCAA

As we mentioned above, the two predominant forms of amino acid supplements on the market are ones containing essential amino acids (EAAs) and those containing branched-chain amino acids (BCAAs).

What are Essential Amino Acids?

Amino acids are grouped into two main categories -- Essential Amino Acids (EAAs) and nonessential amino acids.

EAAs are dubbed "essential" because the human body cannot produce them on its own, meaning they must be obtained through the diet (food or supplements).

Nonessential amino acids, on the other hand, are amino acids the body can generate from other amino acids, carbohydrates, and fats.

There are a total of nine essential amino acids. Those nine EAAs are:

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

Why are EAAs Important?

Simply put, EAAs are required for protein synthesis, meaning that if you’re lacking in any one of the nine essential amino acids, your body won’t do much in the way of protein construction, muscle repair, or muscle building. While protein synthesis is critical for your fitness goals, that only begins to scratch the surface of the many roles and functions EAAs perform in the body.

Essential amino acids also support energy production, cellular repair, and aid in nutrient digestion and absorption.

Additionally, EAAs help protect the mitochondria of each cell in your body. Remember, mitochondria are the “mini power plants” inside each cell to produce ATP.[1]

Without EAAs your body does not have the raw materials needed for basic human function, let alone building lean muscle.

This is why consuming sufficient amounts of EAAs are absolutely critical for everyday life.

For bodybuilders, athletes, and even recreational lifters, the requirement for EAAs is significantly greater than for sedentary individuals due to the increased wear and tear their bodies are subjected to daily from weight lifting.

While you could get all the EAAs you need from your diet alone, oftentimes, a person’s diet may lack diversity (or they may have a low appetite), setting them up for certain amino acid deficiencies.

This is when it's beneficial to have an essential amino acid supplement.

What are BCAAs?

BCAAs stands for "branched-chain" amino acids. They are a subset of the essential amino acids that make up about one-third of muscle protein and are comprised of:

• Leucine
• Isoleucine
• Valine

BCAAs are some of the most well-researched of all the amino acids, due to their ability to activate the mechanistic target of rapamycin (mTOR) pathway. The mTOR pathway is the intracellular signaling pathway that drives muscle protein synthesis in the body.[3]

Additionally, the three BCAAs are also metabolized a bit differently in the body than the other essential amino acids.

Upon ingestion, BCAAs bypass metabolization in the liver and are transported to your muscles. Inside the skeletal muscle, they are converted into branched-chain oxo acids (BCOA), where they serve as a source of fuel for the production of ATP (the “cellular currency” of energy production).

Now, the fact that BCAAs can serve as an energy substrate in skeletal muscle is noteworthy, as it means they may help to limit muscle protein breakdown as well as glycogen depletion during prolonged exercise.[14]

Additionally, BCAAs may also help improve mental and physical performance by reducing fatigue as leucine competes with tryptophan for uptake into the brain.[14,15]

In case you weren’t aware, tryptophan is the amino acid used by the body to produce serotonin. Increases inserotonin are linked to increased central fatigue. Therefore, supplementing with BCAA (primarily leucine) may help limit the production of serotonin, and help reduce perceived exertion and the onset of fatigue, allowing for greater performance.

Overall, the main attributes of BCAAs are:

• Stimulate the mTOR pathway and muscle protein synthesis
• Limit muscle protein breakdown
• Spare muscle glycogen
• Serve as an energy substrate for skeletal muscle
• May help limit CNS fatigue

Now, if the branched-chain oxo acids are not immediately required for energy, they are sent back to the liver for oxidation and energy production.

Muscle Protein Synthesis and Amino Acids

To build protein, your body requires all nine essential amino acids be present in sufficient amounts.

BCAAs (particularly leucine) can stimulate muscle protein synthesis via activation of the mTOR pathway in the body, and they may also help limit muscle breakdown during periods of low-calorie intake when the muscle is at a heightened risk of breakdown.

But, to complete the protein building process, the other six amino acids also need to be present.

This is why we prefer to supplement with EAAs aminos vs BCAAs.

EAA supplements provide all nine essential amino acids that the body requires to synthesize muscle protein. Plus, EAA supplements include BCAAs as the three branched-chain amino acids are a subset of the EAAs.

So, when using an EAA supplement (like EAA Max), you're getting all three of the BCAAs plus the other six essential amino acids needed to support muscle growth and recovery!

Benefits of Essential Amino Acids (EAAs)

• Increased muscle protein synthesis
• Reduced muscle protein breakdown
• Enhanced performance
• Improved metabolism and energy production
• Accelerated recovery
• Better muscle growth
• Enhanced mitochondrial function

Essential Amino Acid Breakdown

Ok, so EAA’s are essential, but do you know what each one does in the body?

Yes, they’re involved heavily in building proteins and muscle, but each mighty little amino has something else to bring to the party too!

Let’s take a deeper look at each individual essential amino acid, beginning with the “king” of amino acids in:

• L-Leucine
  The best known, most studied, of the amino acids is Leucine. It’s also the primary reason BCAA’s have gotten so much hype over the years.
  
  Leucine is a potent stimulator of the mechanistic target of rapamycin (mTOR).[2] FYI, mTOR previously stood for the mammalian target of rapamycin.
  
  mTOR is a cellular signal pathway that functions as the main regulator of cell metabolism, survival, growth, and multiplication.[3] There are several different mTOR pathways in the body, but the one we’re primarily interested in when discussing muscle growth is mTOR1. This particular pathway is the driver of muscle protein synthesis (i.e.muscle building).
  
  Leucine is also beneficial for combatting catabolism too, making it extremely useful for staving off excessive muscle protein breakdown during training.
  
  
• L-Isoleucine
  Leucine’s weaker “younger brother”, Isoleucine can also stimulate protein synthesis in the body, but not to the degree that Leucine can. Isoleucine shines in its ability to enhance glucose uptake and utilization during intense exercises, such as weightlifting or high-intensity interval training (HIIT).[4]
  
  
• L-Valine
  The third leg of the BCAA triumvirate is Valine. While it hasn’t been as heavily studied as Leucine, Valine has been well documented to improve glycogen synthesis in skeletal muscle, prevent catabolism, and support energy production.[4]
  
  
• L-Histidine
  Histidine is a precursor to histamine and essential for cognitive function and wakefulness, as it’s required for the production and maintenance of the myelin sheaths that envelop nerve cells.[9] Histidine also supports the signal transmission from the brain to the various regions of the body.
  
  On top of that, this essential amino acid also aids carnosine production[10], a powerful intracellular buffer. Histidine binds to beta-alanine to form carnosine, which enhances your ability to remove metabolic waste products, such as lactic acid, during training, allowing you to train longer before succumbing to fatigue.

• L-Lysine
  L-Lysine is best known as an amino that enhances calcium absorption and recovery from injury, most likely due to its role in protein construction.[5] It’s also required for carnitine production, making it essential to fat metabolism. Remember, carnitine is a substance that aids the conversion of fat into useable energy.
  
  One other thing to note about lysine is that it is a key player in the formation of cartilage, collagen, skin, and tendons.
  
  
• L-Methionine
  Like all of the other EAAs, Methionine is involved in countless essential functions in the body, but the most well-known of these is as a lipotropic nutrient -- a compound that aids fat digestion in the liver. Methionine also serves as a precursor to the amino acid / antioxidant L-Cysteine, which the body uses to combat free radicals and oxidative stress that can accumulate as a byproduct of exercise.[11]
  
  
• L-Phenylalanine
  Phenylalanine is key to proper Central Nervous System (CNS) function. Upon entering the body, phenylalanine crosses the blood-brain barrier (BBB) where it’s used to synthesize important neurotransmitters including adrenaline (epinephrine), noradrenaline (norepinephrine), and dopamine.[6] These three neurotransmitters govern how you view and interact with everything around you. Plus, these three neurotransmitters also enhance mood, energy, and focus, three key factors for a productive workout.
  
  
• L-Threonine
  The last amino acid to be discovered was Threonine.[6] As one of the EAAs, threonine is necessary for protein synthesis, but more specifically, it’s used to produce glycine and serine, which drive muscle protein synthesis in the body. Also worth noting is that threonine works alongside aspartate and methionine to support fat digestion in the liver, a process also known as lipotropic function.
  
  
• L-Tryptophan
  L-tryptophan is the lone precursor to serotonin, a key neurotransmitter for behavior, mood, and cognition.[7] Unfortunately, tryptophan is the least plentiful amino acid in the body, which makes supplementing with it that much more important.[8] Without adequate tryptophan you can suffer from serotonin deficiency, setting you up for some serious bouts of depression!

 

EAA Max -- Your EAA Solution!

EAAs are essential for protein synthesis, muscle growth, and optimal day-to-day function. They’re also an ideal choice for peri-workout (intra workout) nutrition, which is why Primeval Labs has created EAA Max. Each scoop of EAA Max provides your muscles with all nine EAA’s required for muscle repair and growth, including a full 5g of 2:1:1 BCAAs!  

And don’t worry about the typical “off” flavor that amino acid products usually have. Primeval Labs has sourced the highest quality amino acids so you’ll never get that “amino funk” when drinking EAA Max. Premium quality, superior formulation, and industry-leading taste make EAA Max the best EAA supplement on the market!

Shop All Our Amino Products:

References

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2. Corsetti G, Stacchiotti A, D’Antona G, Nisoli E, Dioguardi FS, Rezzani R. Supplementation with essential amino acids in middle age maintains the health of  rat kidney. Int J Immunopathol Pharmacol. 2010;23(2):523-533. doi:10.1177/039463201002300214. http://journals.sagepub.com/doi/pdf/10.1177/039463201002300214
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10. Van Ruitenbeek P, Sambeth A, Vermeeren A, Young S, Riedel W. Effects of L-histidine depletion and L-tyrosine/L-phenylalanine depletion on sensory and motor processes in healthy volunteers. British Journal of Pharmacology. 2009;157(1):92-103. doi:10.1111/j.1476-5381.2009.00203.x. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2697785/
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