Nowadays, it appears as though the building blocks of proteins, commonly referred to as “amino acids,” are tiny little gold nuggets endowing those who are fortunate enough to come across them in a sports gel, capsule, fizzy drink, or cocktail with superhuman abilities. After all, nutrition supplement producers are beginning to incorporate these little fellas into nearly everything, from your designed pre-workout snack to your during-workout beverage to your post-workout smoothie mix.

However, why are amino acids so popular now?

And, maybe more significantly, do amino acids work?

We’re about to find out, and have some fun while doing so.

When I was in biology class, it was useful to think of a muscle as a large Lego castle (or Lego pirate ship, depending on your preference), and amino acids as the individual lego pieces that comprised the vast Lego construction (your muscle). Yes, it is convenient. No, it is not exhaustive. Beyond their function as building blocks, amino acids are required for the creation of proteins, enzymes, hormones, neurotransmitters, metabolic pathways, mental stability, and virtually every other function in the human body. Thus, if Legos are analogous to amino acids, a more accurate analogy would be to throw all the Legos out of the box and watch them self-assemble into a magical pirate ship, then float into the air and fly around the room blasting small cannon balls.

In other words, amino acids serve a purpose that extends much beyond their role as “building blocks.”

In the nutrition supplement industry (which, when I use that term, conjures up images of big fat guys in black suits gathered around an oak conference table, but in reality, the majority of these individuals are skinny athletes wearing white shoes and shorts), amino acid supplements are classified into two broad categories: Essential Amino Acids (EAA’s) and Branched Chain Amino Acids (BCAA’s).

Amino Acids That Are Required

As the name implies, essential amino acids are necessary because, unlike the other amino acids, they cannot be synthesized by human bodies. Rather than that, we must obtain them through our diet. Have you ever heard of Pvt. Tim Hall, also known as Private Tim Hall? If you’re a biology or chemistry nerd, you’ve probably heard of him, as he’s the pneumonic that’s frequently used to recall the important amino acids, which are Phenylanine, Valine, Threonine, Tryptophan, Isoleucine, Histidine, Arginine, Leucine, and Lysine. Thank you, Tim; if we ever win money in Biology Trivial Pursuit, we’ll send you a check.

Anyway, let’s take a look at why Pvt. Tim can be beneficial to us during workout, beginning with P.

Phenylalanine has historically been marketed for its analgesic (pain-killing) and depressive properties, as well as its role as a precursor in the production of norepinephrine and dopamine, two “feel-good” brain chemicals. This may be beneficial because increased norepinephrine and dopamine levels in the brain may actually decrease your “RPE” or Rating of Perceived Exertion During Exercise, which means you may feel happier while suffering through a brutal exercise session or Ironman bike ride.

Together with Isoleucine and Leucine, valine is a significant factor since it is BOTH an Essential and a Branched Chain Amino Acid. Valine is an absolutely necessary amino acid. It may aid in the prevention of muscle protein breakdown during exercise. This means that if you take Valine during exercise, you may recover more quickly since muscle damage is reduced. Additional information is available in the section below on BCAA’s.

There is a dearth of study on threonine. Personally, I couldn’t discover any evidence that threonine may aid in workout performance, but I’m guessing it’s included in essential amino acid supplements because it is, after all, important. And many of the research on EAA’s employ all of them rather than focusing exclusively on one, such as Threonine. For example, and this is somewhat interesting for those who are sufficiently masochistic to enjoy working out while starving, there is a significant muscle-preserving effect of an EAA + Carbohydrate solution ingested during fasted training, as well as decreased indicators of muscle damage and inflammation. This essentially indicates that if you took some important amino acids, even if you did not eat anything, you may not “cannibalize” as much lean muscle during a fasting training session.

Tryptophan is an intriguing amino acid. It is a precursor of serotonin, a brain neurotransmitter that can help to alleviate pain and, if taken before bed, can even cause drowsiness. The primary reason to take tryptophan is to boost pain tolerance during strenuous workouts, games, or racing. However, research to far has been divided on whether or not this genuinely increases performance.

Isoleucine, another BCAA/EAA combination, shares some of Valine’s benefits. In a moment, I’ll discuss BCAAs in further detail.

Histidine, as the name implies, is a precursor to histamine. It possesses some antioxidant qualities and is required for the synthesis of carnosine. In retrospect, that statement I just typed is not very user-friendly and is largely comprised of technical jargon. To clarify, histamine may aid in the battle against the cell-damaging free radicals produced during exercise, while carnosine aids in the rapid elimination of muscle burn and the conversion of lactic acid back to usable muscle fuel. Thus, a gold star is awarded to histidine.

Then there’s arginine, and if you’re an elderly gentleman who relies on a small blue sill to have a more pleasant time in the sac, you can thank arginine. Arginine aids in the production of nitric oxide, which is a vasodilator that enhances blood flow and may aid in exercise capacity (in the case of the blue pill, for one specific body part). The majority of studies on arginine demonstrate that it does indeed help those with cardiovascular disease increase their exercise capacity, and similar to tryptophan, the studies are divided on whether it actually improves the athletic population – but it shows a lot of potential.

Leucine is another example of a BCAA/EAA combination. We’ll get to BCAAs in around 30 seconds, depending on your reading speed.

Lysine is a supplement that my mother used to use to alleviate cold sores caused by lemony foods. That is mostly because it aids in the healing of oral tissue. However, for exercisers, lysine may actually aid in growth hormone production, which might significantly improve muscle repair and recovery, but the amount of lysine required to increase growth hormone release would produce gastrointestinal distress, or as I like to call it, sad poopies. However, when paired with the other necessary amino acids, a growth hormone response may occur at lower dosages, and there is some clinical evidence that essential amino acid supplementation may increase growth hormone-releasing factors.

That concludes our discussion on important amino acids. I neglected to explain that they may have a mild insulin and cortisol boosting effect. Before you recoil in disbelief and flush all your essential amino acids down the toilet because you’ve heard insulin and cortisol make you fat, keep in mind that both insulin and cortisol are necessary (in smaller amounts) for the “anabolic process,” or the growth, repair, and recovery of lean muscle tissue. The amount of essential amino acids obtained is somewhat different from the stress and insulin/cortisol response induced by eating a pint of ice cream while drinking scotch and working all night on a job project.

Amino Acids with Branched Chains

Leucine, isoleucine, and valine are all BCAAs. They’re interesting (at least to those wearing white lab coats) since they’re digested in muscle rather than the liver. This suggests that BCAAs can be used as a primary source of energy during exercise, perhaps preventing premature muscle breakdown. Indeed, there was one persuasive study conducted by a man named Ohtani that shown exercising individuals who received BCAAs had increased exercise efficiency and capacity when compared to a control group that did not get BCAAs.

Other studies have discovered that BCAA’s can increase a slew of important factors for an exercising athlete, including red blood cell count, hemoglobin, hematocrit, and serum albumin, as well as lower fasting blood glucose and creatine phophokinase, which results in less inflammation, improved red blood cell formation, and increased storage carbohydrate formation. BCAA supplementation following exercise has been proven to increase muscle strength recovery and, more intriguingly, the potential to halt muscle breakdown even during rigorous training and “overreaching” (getting very close to overtraining). Simply Google Sugita and Kraemer’s branched chain amino acid studies for additional information (yes, shocker, this is a newsletter article, not a peer-reviewed scientific journal report with complete citations, because if it were the latter, you’d be sleeping by now – so if you’re a science nazi, get busy on Google scholar).

Now, on to the many cool things that BCAA’s can do: they reduce blood indicators of muscle tissue damage following prolonged periods of exercise, indicating less muscle damage, and they also help maintain higher blood levels of amino acids, which, as previously stated, can make you feel happier even when you’re suffering during exercise. Logic dictates that low BCAA levels are associated with greater fatigue and decreased physical performance.

Indeed, BCAAs are used in medicine. They may aid in the recovery of patients suffering from liver disease, may aid in the improvement of patients suffering from lateral sclerosis, and may aid in the recovery of patients suffering from trauma, intense physical stress (can you say “Ironman triathlon”), kidney failure, and burns.