The Importance of BCAAs

Sometimes it seems like BCAAs are the biggest not-secret secret in fitness publications and forums, and that’s a damn shame. From what I can tell, it seems that most people are largely unaware of the benefits of straight BCAA supplementation and/or they believe that they don’t need to because amino acids are in protein and they figure they’ll get enough that way. The latter isn’t untrue, but it isn’t entirely accurate. So let’s delve into BCAAs for a bit and get to the bottom of why they’re so special.

BCAAs, or Branched Chain Amino Acids, consist of three amino acids- Leucine, Isoleucine, and Valine. They differ from other amino acids not only in how they are structured (they branch out from a central carbon atom) but also how they affect protein synthesis. While all amino acids (the building blocks of protein fuck yeah high school biology) are useful and necessary, BCAAs are the most important amino acids for muscle growth.

Among the three BCAAs, the most researched and the most important is leucine. I want you to check the links at the bottom for a fuller understanding if you have the time and the patience to read through scientific papers, but for now I want to highlight the two most important functions of leucine for those of us wanting to get swole:


Our bodies go through phases of protein synthesis (growth) and catabolism (breakdown) throughout the day and especially during, you guessed it, workout and post-workout periods. During training, your muscles go through catabolism- amino acids are used up and are oxidized by your muscles, and as the concentration of these amino acids drops below necessary levels the muscles break down. Catabolism itself isn’t necessarily bad and is indeed necessary for growth, but the less catabolism the better. Protein synthesis does not actually begin until after you are done working out *and* you consume enough amino acids/protein afterwards. This is why you take protein after you lift. Furthermore, and most importantly, there is one amino acid that is crucial for starting up the synthesis process- Leucine. You need leucine in order to begin synthesis.

Insulin Production

Insulin is an important chemical for muscle growth, and the faster it gets to your muscles and the more of it, the better. Insulin helps prevent muscle breakdown during and after the workout, creating a better environment for synthesis to occur. So it’s like a synthesis booster in a way. And of course there is one BCAA important to the stimulation of insulin levels- Leucine. Leucine causes your body to make more of it, and to add icing on the cake, when insulin and leucine are working together at the same time synthesis is increased compared to insulin release alone.

Now I know I just summed up long-ass papers in two paragraphs, but I hope you realize the importance of BCAAs and especially leucine right now.

So what does this mean for you? How is this applied? Why is it important to take BCAAs?

By taking BCAAs before you lift, you are slowing down catabolism first and foremost; you’re giving your muscles something to work with. Also, catabolism is going to happen during a lift, but not as drastically with BCAAs, giving your muscles a better “launching off point” for synthesis after the workout. Also, those that take BCAAs pre-workout, including me, can attest that it straight up gives you better workouts. The time I forgot to take my BCAAs was the worst lift I had had since I began supplementing with it, and it all made sense after I read these papers- they keep my muscles going at a higher level when I take them.

By taking BCAAs after you lift, you are giving your muscles that extra kick for synthesis along with the insulin bost. Leucine is so important to this process, you’re short changing yourself if you’re not getting enough.

The reason why taking extra BCAAs is worth it is that protein supplements alone do not supply you with the recommended 10-15g of BCAAs pre-workout. As much as I love casein, one scoop barely gives me 5g. Gold Standard Whey comes in at 5g BCAA as well. Don’t get me wrong you need that stuff too, but in order to give yourself the required amount of leucine to take shit up a notch, you would need at least two scoops, which is just not economical and would probably make you feel bloated anyway. Also, when taken in their pure forms the BCAAs literally go straight to your muscles as there is no need for extra digestion/breakdown.

Since beginning to supplement BCAAs in the spring, along with Beta-Alanine, my lifting totals have been awesome. I progress faster and as I mentioned before, feel much less fatigued during the workout. I gotta hand it to Leangains for getting me started on it, and now BCAAs are a staple of my supplement regime that I’ll never stop taking.

Recommendations for taking it differ, but for real this is one of those things where there is hardly a “wrong way” to do it. For me, I mix up around 10g pre-workout and take it on an empty stomach. Some people like to take it continuously as they lift. Some people take it before and after- if I was rolling in dough that’s what I’d do. Some people like it flavored, others get the unflavored kind and sprinkle it in with their pre-workouts. Some do the pills instead of the powder. Experiment a little, find out what works for you.

I’ve tried a couple brands, but by far and away the most bang for my buck has come from-

Optimum Nutrition Instantized BCAA 5000mg Powder, Unflavored, 336g

Check it out, you won’t be disappointed.

For further reading:

Leucine Regulation of Protein Synthesis

BCAA and Athletic Performance 

Swole Life.

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About The Author

They call me Fly, Fresh, and Young. Gym rat by day, lecherous drunkass by night. Follow me on Twitter @nate_moneyh.


  1. Virgle Kent October 26, 2012 at 12:53 pm

    question FFY,

    I always wonder how long you can supplement on stuff. I know it’s good to put your body on these supplements like BCAA for six to eight weeks then take off for a few weeks to let your body go with out and then get back on if you want. This makes it more effective for better gains. If your body is used to preforming on a supplement for so long then decrease in gains over time.

    I even go a few weeks without regular whey protein a few times a year

    What are your thoughts.

    • FFY October 30, 2012 at 8:11 pm

      There are some interesting theories out there about cycling protein, but none of them recommend getting less or anything like that.

      BCAAs and protein are incredibly important to buliding muscle, straight up, and you need to get them regardless of how. BCAA powder just gives it to you nice, conveniently, and measurably.

      I can’t recommend cycling protein or BCAAs.

      Contrast that to B-A or creatine supplementation, when you are artificially boosting their levels above where they would be naturally, causing your body to react with favorable results for awhile before it gets used to it.

  2. AverageMarriedDad October 26, 2012 at 3:20 pm

    Nice post, I learned a lot here. I guess I didn’t realize that BCAA’s have that much of an impact, may have to try them out (been doing Outlaw and seem to be in a constant state of muscle fatigue).

  3. Shameful October 26, 2012 at 5:56 pm

    Doing 10g preworkout, going to have to try 10g post now to. Taking the same brand, and just a heads up, it tastes like ashes. I just deal with it, but be prepares.

  4. A axe October 26, 2012 at 7:52 pm

    For more of the science check out

    Not to mention reddit for swole acceptance

  5. Mitch October 28, 2012 at 9:35 pm

    Besides helping to build muscle, do BCAA’s supposedly help your performance during physical activity?

    Let’s say you’re playing basketball, or practicing a martial art. Would you take this before physical activity like that which isn’t strictly lifting?


    • FFY October 30, 2012 at 8:15 pm

      Interesting question. The performance benefits it gives during lifting are largely due to the way it helps stave off catabolism, if only a little.

      Athletic events are going to involve your fitness and endurance levels a lot more than lifting, so I am not sure if there would be any benefits. If you’re not in basketball shape, it’s not gonna do anything. On the other hand, perhaps there could be something on the margins. Who knows. Try it out and report back if you feel like it.

  6. soccer keychains October 17, 2013 at 9:42 am

    this belongs to the best really reads I’ve possessed n time, i will ensure that you recommend it to two people, best wishes

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