Are BCAAs Worth Taking? [Pros and Cons for First Timers]

Next to protein powders and pre-workouts, BCAAs — or branched chain amino acids — are among the most popular types of supplements among gym enthusiasts.

Supplementing with BCAAs is believed to enhance muscle protein synthesis — the process of building new muscle protein — decrease muscle protein breakdown, and enhance exercise recovery.

However, you may wonder whether these claims are true and if supplementing with BCAAs is worth your time or money.

This article discusses everything you need to know about BCAA supplements, including the benefits and downsides.

What Are Branched Chain Amino Acids (BCAAs)?

Amino acids are the building blocks of protein. Think of amino acids as bricks and protein as a brick wall. There are hundreds of amino acids that can build this wall, but your body only needs about 20 to make all the proteins it needs to repair and build tissues like muscle, skin, and bone (1).

Of the 20 amino acids, there are nine that you must get from your diet since your body cannot produce them. These nine are called essential amino acids, and of these nine, three are BCAAs — leucine, isoleucine, and valine. Of these, leucine is believed to be the one that "triggers" the muscle-building process.

As a component of protein, BCAAs are found in protein-containing foods, primarily those of animal origin, such as meats, poultry, and fish. You can also find them in supplement form, usually in a 2:1:1 leucine, isoleucine, valine ratio. Supplements with BCAAs may contain them alone or in combination with other ingredients intended to increase muscle growth and recovery.

The Benefits of BCAAs

BCAAs offer many benefits when it comes to supporting your fitness goals.

Here are the primary benefits of taking BCAA supplements:

1. May Decrease Muscle Protein Breakdown

Research suggests that BCAAs can inhibit muscle protein catabolism, which can be useful for building muscle (2).

Throughout the day, your body naturally goes through periods of muscle protein catabolism (breakdown) and muscle protein synthesis (building). Using the brick wall as an example, muscle protein synthesis is adding bricks to the wall, while muscle protein catabolism is removing them.

Various factors determine whether bricks are added or removed, but neither process is turned "on" or "off." However, the speed at which one occurs can increase or decrease, and it's this difference in speed of the adding and removing bricks that determines whether your muscles grow, stay the same, or become smaller.

If muscle protein synthesis exceeds muscle protein catabolism, the wall (your muscles) grow, whereas if the opposite occurs, the wall shrinks (you lose muscle mass).

Thus, if you want to build muscle, you need to ensure that the rate of muscle protein synthesis is greater than muscle protein catabolism over a long period of time.

By inhibiting muscle protein breakdown, BCAAs could lower the threshold at which muscle protein synthesis occurs (3).

2. May Decrease Muscle Soreness

Muscle soreness is something every person that has set foot into a gym has experienced. This soreness — called delayed onset muscle soreness (DOMS) — typically occurs when you expose your muscles to a stress they aren't accustomed to and it can last up to 72 hours after exercise (4).

Fortunately, the soreness goes away over time as you adapt to these stresses or workouts — unless it's after a leg workout, in which descending stairs or sitting on the toilet the next few days never becomes any less painful.

Still, there are nutritional strategies that can ease muscle soreness, with BCAAs being one of them. Many studies have shown that BCAAs decrease muscle protein breakdown during exercise and decrease markers of muscle damage — such as creatine kinase and lactate dehydrogenase (5, 6).

To this point, a review of 25 studies comprised of nearly 500 participants demonstrated that BCAA supplementation significantly lowered muscle soreness 24 and 48 hours post-exercise compared with a placebo (7).

3. May Reduce Exercise Fatigue

Just as BCAAs may decrease exercise-induced muscle soreness, they may also decrease exercise-inducted fatigue.

There are various factors that contribute to how soon you fatigue from exercise, but taking BCAAs may prolong the time it takes. This is because your muscles use BCAAs during exercise, causing them to decline. This decline increases levels of the amino acids tryptophan in your brain. Here, tryptophan is converted to serotonin, a brain chemical that is believed to contribute to exercise-induced fatigue.

To this point, one study demonstrated that male runners who supplemented with 20 grams of BCAAs one hour before a running test were able to run longer and harder than when they supplemented with a placebo (8).

The Downsides of BCAAs

BCAAs can decrease muscle protein breakdown and may decrease exercise-induced fatigue and soreness, but there are some downsides to consider in determining whether BCAAs are right for you.

1. They Aren't Effective for Increasing Muscle Protein Synthesis

BCAAs are most commonly taken to promote muscle growth and recovery. And while they can decrease muscle protein breakdown, there isn't strong supporting evidence that they have an anabolic — or muscle-building effect. Even though leucine is seen as the "trigger" for muscle protein synthesis, the other essential amino acids are necessary to build muscle (2).

To this point, a study examined the muscle protein synthesis response to different BCAA supplementation protocols in young men. One of the protocols used 6.25 grams of whey protein with 2.25 grams of leucine, and a second used 25 grams of whey protein, which contained the same amount of leucine as the first. Interestingly, the muscle protein synthesis response to the 25 grams of protein was double that of the first protocol indicating that leucine alone doesn't determine the anabolic effect of protein.

However, this same study also demonstrated the addition of 4.25 grams of leucine to 6.25 grams of whey protein provided the same muscle protein synthesis response as 25 grams of whey protein.

Thus, unless you're consuming an inadequate amount of protein and essential amino acids, supplementing with BCAAs — specifically leucine — becomes less useful.

2. The BCAAs Compete for Absorption

When we're talking bout BCAAs, leucine is really the star of the bunch since it's the ignitor of muscle protein synthesis. So, you might believe it's best to supplement with leucine alone. But, doing so decreases concentrations of the other two amino acids, which then limits muscle protein synthesis.

Therefore, supplementing with all three BCAAs is necessary to overcome the decrease in valine and isoleucine concentrations that would occur when consuming leucine alone. Still, there exists another problem — leucine requires the presence of another amino acid called glutamine to find its way into your muscles. So, if flood your body with BCAAs and don't have enough glutamine around, leucine can't enter the muscle cell or does so at a very slow rate.

Most BCAA supplements don't provide glutamine, which renders them less effective for either decreasing muscle protein breakdown or alleviating muscle soreness and fatigue from exercise.

Fortunately, Transparent Labs BCAA Glutamine contains clinical doses of both Leucine and Glutamine!

Are BCAAs Worth It?

Supplements are intended to provide nutrients that you may lack or could benefit from consuming more of, and BCAAs are no different.

If you're consuming enough high-quality protein from sources like chicken, beef, fish, yogurt, and certain plant-based foods like peas or soy, you probably won't benefit from BCAAs if your goal is to build muscle. Remember, you need the other six essential amino acids around to build muscle and leucine isn't always well absorbed.

But, if you want to experiment with BCAAs, identify the reason for doing so and try and track it. For example, because there is evidence to support BCAAs for decreasing muscle soreness, you could try taking them around your workouts to see if doing so helps. This way, you can determine whether the supplement is working and if it's worth keeping in your supplement regime.

Some people may not have a specific gym goal but take BCAAs because they are commonly flavored and drinking the supplement helps them meet their fluid intake easier. In either case, if you decide to give BCAAs a try, consider choosing a product that contains them alongside glutamine to ensure most of the leucine reaches your muscles and doesn't go to waste.

Key Takeaway

BCAA supplementation offers many potential benefits for fitness enthusiasts. These amino acids may decrease the barrier for muscle protein synthesis, while also reducing post-exercise muscle soreness and delaying fatigue during workouts.

However, BCAAs alone may not significantly increase muscle protein synthesis, necessitating the inclusion of other essential amino acids.

Additionally, for optimal absorption and effectiveness, BCAA supplements should ideally contain glutamine. Experimentation with BCAAs can help individuals gauge their impact on workout performance and recovery, but those already consuming ample protein may experience limited additional benefits.

Frequently Asked Questions

Are BCAAs Worth It?

Taking BCAAs are worth it if you're trying to decrease muscle protein breakdown and alleviate muscle soreness and fatigue.

Are BCAAs Safe?

BCAAs are likely safe and don't cause insulin resistance in healthy people. It's best to refrain from supplementation if you are pregnant or breastfeeding due to the limited research in these populations (9).

Are BCAAs Protein?

BCAAs are individual amino acids — leucine, isoleucine, and valine. Amino acids are not protein but they combine to form protein.

Do BCAAs Give You Energy?

BCAAs haven't been shown to give you energy but they may reduce exercise fatigue, allowing you to exercise longer or harder before fatiguing (8).