What Are Branched Chain Amino Acids (BCAAs)?

What are Branched Chain Amino Acids? Leucine and BCAAs are two of the more widely researched amino acids used for sports supplementation, particularly in terms of bodybuilding and strength/power based sports. They are also some of the most widely used amino acids in sports supplementation, and for very good reason. BCAAs are comprised of leucine, valine and isoleucine, all essential amino acids (amino acids that must be obtained from the diet), and form 35% of the amino acids found in muscle proteins. Already we can see how important these amino acids are before we even begin to touch upon the science! BCAAs are usually formed in the ratio of 2:1:1, of leucine, valine and isoleucine. Although leucine forms half of the BCAA formula per dosing, it can be and is often supplemented on its own, without any reduction in its benefits. branched-chain-amino-acids

BCAA Chemical Structure

Why are they useful? BCAAs are responsible for building, maintaining and repairing lean muscle, and preventing catabolism (muscle protein breakdown). That said, their importance should become immediately obvious to anyone involved in strength or power based activities and sports. There are numerous studies investigating the effects of leucine and BCAA supplementation on strength trained athletes all strongly support their use as a supplement for bodybuilding or similar activities. These studies have shown that supplementing approximately 2-5g of leucine before and following resistance exercise increases muscle protein synthesis, therefore increasing strength and muscle growth (Lucaszuk et al, 2012, and Layman and Norton, 2006). Other studies compared BCAA supplementation with a placebo group in previously resistance trained males. They found that in the BCAA group potentially damaging bi-products of exercise (such as the dreaded cortisol) levels in the blood were significantly lower, and testosterone levels were significantly higher than the control group. This created an extremely beneficial anabolic hormone profile as well as reducing muscle damage caused by training, leading to an increase in performance and therefore (and sometimes more importantly) muscle growth (Pearson and Sharp, 2010). This was similarly found by Harris et al (2004), who also suggested that BCAA requirements were increased by resistance exercise providing yet another reason for its use in supplementation. With resistance training being the stimulus to promote muscle growth, these studies show that supplementing with either BCAAs or leucine is extremely important in maximising your body’s response to this. And maximising you body’s response to this means bigger and stronger muscles, something we all desire! When and how much? The majority of studies have shown that BCAA and leucine supplementation is most effective during and following resistance exercise. Supplementing BCAAs or leucine during workouts has been shown to prevent muscle protein breakdown by the stresses of exercise. This means that workout intensity can be maintained for much longer, and therefore providing a greater stimulus for muscle growth. Providing nutritional needs are met (i.e. post-workout BCAAs, and whole proteins) this greater stimulus and be turned into greater muscle growth. Products such as Anabolic Designs’ Aminotaur, Gaspari Aminolast and iForce Compete are all intra-workout formulas that provide a hefty minimum 5g of BCAAs or leucine per serving. The results of the studies highlighted above showed that significant benefits were obtained from serving sizes as little as 2g, so imagine the potential of servings as high as 5g! These studies also only examined leucine in the form of l-leucine, but both Anabolic Designs’ Aminotaur and Gaspari Aminolast contains leucine in forms even more potent and absorbable than standard l-leucine, further increasing the benefits.


Gaspari Nutrition Aminolast

Perhaps the most important time for BCAA and leucine supplementation is post workout. As the studies above show, post workout consumption of BCAAs or leucine lead to huge increases in muscle protein synthesis when compared to a carbohydrate placebo. An increase in muscle protein synthesis leads to an increase in muscle size and strength. Its goes without saying that as strength athletes, this is exactly the outcome we desire. Even if your goal is endurance, this increase in muscle protein synthesis will lead to an increased rate of muscular repair allowing for a greater level of recovery. BCAAs are essential for muscular formation and function and so are a vital nutrient following strenuous exercise and must be replaced. Products such as Anabolic Designs’ Syntha Charge and MusclePharm BCAA caps all amply provide the BCAA or leucine in the quantities required to obtain these benefits. So, should I supplement with these? Yes, to put it simply. Supplementing with BCAAs and leucine has a huge amount of scientific research backing their use. They have been shown in numerous studies to provide exciting benefits when combined with resistance training in particular. Their ability to influence muscle protein synthesis, and therefore muscle size and strength, cannot be understated. Any athlete looking to gain lean muscle mass and/or strength should seriously consider adding BCAA or leucine products to their supplement regulars. In fact, it is this author’s opinion that their importance ranks next to that of even the mighty creatine, and should be in every self respecting strength athletes supplement stack.  Even if endurance is your goal, they should still be heavily considered due to its muscle sparing and repairing effects.


Anabolic Designs Aminotaur

At Cardiff Sports Nutrition we stock a range of amino acid based supplements, take a look at our amino acid supplements here.

Beau Scott BSc