WHAT ARE AMINO ACIDS, AND SHOULD I BE TAKING THEM?

If you've been in the gym scene for a while, you've likely heard the words' amino acids' floating around? Or perhaps BCAAs? Or maybe even EAAs? If like many, you nod and smile without actually fully understanding what they are, we're here to tell you; you're not alone.

Yet, if there's one supplement worth understanding a little more, we reckon it's this one. From supporting your performance to aiding your muscle recovery, amino acids might be the missing link between you and your goals. Want to be in the know when it comes to aminos? Keep reading!

In its simplest form, amino acids are compounds that combine to form proteins. Often referred to as the "building blocks of life," amino acids are naturally found in our bodies and are required to produce enzymes, hormones, neurotransmitters, and more. Your body digests and breaks it down upon consuming protein, and amino acids are what's left in the body. Amino acids help with the following processes:

Breaking down food

Acting as an energy source

Repairing and growing body tissue

From a training perspective, our bodies are constantly breaking down and building up muscle tissue. As exercise is generally responsible for muscles breaking down, it's essential to get the proper nutrition to help rebuild them and grow. This is where EAAs come in.

Yep, amino acids are generally categorised into three groups:

Non-essential amino acids - this refers to the aminos that our bodies can produce on its own, even if not sourced from food or supplementation. Non-essential amino acids include alanine, arginine, asparagine, aspartic acid, cysteine, glutamic acid, glutamine, glycine, proline, serine, and tyrosine.

Essential amino acids - this refers to aminos that your body cannot produce and, thus, must be sourced from food and/or supplementation. This includes the nine essential amino acids (EAAs): histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine.

Conditionally essential amino acids - this type of aminos are generally not essential, except in times of illness or stress, in which they become depleted and need to be replenished. This includes arginine, cysteine, glutamine, tyrosine, glycine, ornithine, proline, and serine.

As you can see, while there are 20 different amino acids required for your body to grow and function optimally, only nine are considered essential (as mentioned above). These are more commonly known as EAAs.

To understand why EAAs are so, well, essential, it's important to understand what each of them has to offer…

1. Phenylalanine - It plays an important role in the structure and function of proteins and enzymes. It's also a precursor for the neurotransmitters, Tyrosine, Dopamine, and Epinephrine.
2. Valine - One of the three BCAAs, Valine helps stimulate muscle growth and recovery and plays a role in energy production. 
3. Threonine - this one is found in structural proteins like collagen and elastin, and as such, plays an important role in skin and connective tissue health. It is also suggested to support fat metabolism and immune function.
4. Tryptophan - It's required to maintain adequate nitrogen balance and is a precursor to serotonin, which is the neurotransmitter responsible for regulating your sleep, mood, and appetite.
5. Methionine - This ingredient plays an important role in metabolism and detoxification. Additionally, it's also required for tissue growth and zinc and selenium absorption.
6. Leucine - Leucine is another of the three BCAAs required for protein synthesis and muscle repair. But, that's not all. It also helps to regulate blood sugar levels, support wound healing, and produce growth hormones.
7. Isoleucine - The final BCAA of the three, isoleucine plays a role in muscle metabolism and is heavily found in muscle tissue. It's also widely known for its role in supporting immune function, hemoglobin production, and energy regulation.
8. Lysine - this one also plays an important role in protein synthesis, enzyme production, and last but certainly not least, the absorption of calcium. Not to mention, it also boasts benefits in energy production and immune function.
9. Histidine - this incredible ingredient is used to produce histamine, which is an important neurotransmitter crucial to immune response, digestion, sleep-wake cycles, and sexual health and function.

You may have noticed by now that the three BCAAs (isoleucine, leucine, and valine) are technically also part of the EAA group. But, what makes them unique? Simply put, their structure. The three BCAAs are the only amino acids with a chain that branches off to one side. BCAAs make up a large portion of your body's total amino acid pool (roughly 35-40% of all EAAs in your body and 14-18% of that found in your muscles). Unlike most other aminos, BCAAs are generally broken down in the muscle instead of the liver.

However, despite BCAAs prominence in your body, muscle protein synthesis requires more than just BCAAs alone. In actual fact, it requires all essential and non-essential amino acids to facilitate the process. However, that's not to say that BCAAs aren't beneficial. Studies suggest that those who will benefit from BCAAs generally already get adequate protein in their diet, which would compensate for the other amino acids missing.

The International Society of Sports Nutrition recommends that people trying to build muscle consume between 1.4 - 2.0g of protein per kg of body weight daily.

When to take EAAs: If you don't meet your daily protein recommendation, you'll likely see the most benefit from supplementing EAAs. Vegans and vegetarians will generally see more benefit from EAAs.

When to take BCAAs: If your diet is already rich in protein and you meet the recommended daily protein requirements above, BCAAs may offer enough of what you need in your diet… although EAAs are still a more in-depth option!

When sourcing Essential Amino Acids from your diet, this can be via food or supplementation. However, studies have found that taking concentrated doses in supplement form has various health benefits. Let's dive into these a little deeper.

As mentioned above, one of the 9 EAAs is Tryptophan, which is required to produce serotonin. Serotonin plays an important role in regulating mood, sleep, and behaviours.

Various studies have found a link between supplementing with tryptophan and improved sleep and mood. On the contrary, low serotonin levels are linked to mood and sleep disturbances.

In a study of 16 resistance-based athletes, BCAA supplements improved performance and muscle recovery while decreasing muscle soreness, compared to a placebo group (Waldron et al., 2017). To further support this, a recent review of eight studies found that using BCAAs was more effective than rest for promoting muscle recovery and reducing post-workout muscle soreness.

EAAs are found to offer benefits in preserving lean body mass in both athletes and older adults. A 10-day study in 22 older adults on bed rest demonstrated that those who received 15 grams of EAAs maintained muscle protein synthesis, whereas the placebo group saw a 30% decrease in the process.

Why was the study conducted on an older group? Muscle loss is most commonly associated with prolonged illness and bed rest, typically in older people.