EAA and BCAA: For whom and why?

Do you go to a gym? You have undoubtedly noticed the assortments of colored drinks in the shakers of other users of the center. Do you know why they drink it? Often, these are mixtures of amino acids with performance enhancing propreties. Again, more than one mix exists, but the most popular are BCAAs (Branched Chain Amino Acids) and EAAs (Essential Amino Acids). These mixes have similarities, but one will always be more appropriate than the other depending on your training goal, so it is important to understand the path they take and their impact on your performance.

Amino Acid

In the supplements market, a tone of amino acids are sold as a single ingredient or in mixtures, whether for pre / post / intra workout use. Why are they found everywhere? In fact, amino acids are the results of protein digestion. Once absorbed, the body chooses to use them as is or to convert them into other amino acids to participate in the `` construction '' of new proteins, enzymes, small metabolic soldiers which in turn, participate in thousands of chemical reactions in the body. BCAAs like EAAs are groupings of these amino acids. 


This arrangement is made up of 3 amino acids: leucine, isoleucine and valine. Each has their role, however, it is recommended to consume all three in ratios where leucine is dominant. Here are some of the benefits that consumers of BCAAs enjoy.

Push back fatigue

During exercise, the depletion of the reserves of this trio causes an influx of tryptophan to the brain, leading to the secretion of serotonin, itself responsible for premature fatigue. Supplementing with BCAAs during a workout helps ward off this exercise-related fatigue. This consequence is prized mainly in aerobic trainers, for whom an improvement in endurance is most noticeable. In order to benefit from this effect, it is recommended to start consuming BCAAs slightly before training, and to continue ingesting them for the first few minutes. 

Improve protein synthesis 

Leucine influences the metabolic path of protein synthesis and is believed to be causally linked to lean mass synthesis. However, studies are conclusive when individuals are in a calorie deficit or protein deficit. 


Isoleucine is responsible for increasing the absorption of glucose into muscle fibers. This leads to better regeneration of muscle glycogen, and therefore, better post-workout recovery. This reaction is observed within 60 min of consumption, which implies that for individuals consuming their "post-workout" carbohydrates, it is preferable to start ingesting BCAAs towards the end of the workout. 

For who? Prevention mission!

  • Prevent fatigue: For the impact on reducing fatigue during aerobic training, all individuals with a cardiovascular portion in their exercise session should consume BCAAs as a supplement. 
  • Prevent overtraining: For recovery benefits, anyone participating in a physical activity program would benefit from supplementing with BCAAs.
  • Prevent the catabolism of muscle mass: For the induction of better protein synthesis, people in a calorie deficit, therefore following a weight management program, or vegetarians / vegans in protein deficit, supplementation with BCAAs is recommended to maintain muscle mass and reduce its degradation .


They are called essential because it is essential to consume them in our diet, since it is impossible for our body to synthesize them otherwise. Of the 20 amino acids, 9 are considered essential and participate in many metabolic reactions:

  1. Leucine (BCAA): Protein synthesis and glucose metabolism;
  2. Isoleucine (BCAA): Protein synthesis and glucose metabolism;
  3. Valine (BCAA): Synergy with other BCAAs in muscle recovery;
  4. Histidine: Histamine precursor, anti-oxidant;
  5. Methionine: Participates in beta-oxidation (elimination of fat) and detoxification of the liver;
  6. Phenylalanine: Actor in the modulation of pain perception and hormonal balance linked to mood disorders;
  7. Threonine: Involved in immune health and the maintenance of connective tissues;
  8. Tryptophan: Role in the regulation of sleep;
  9. Lysine: Important for the strength of connective tissues and the secretion of growth hormone;

As mentioned above, enzymes are synthesized from amino acids. If there is a noticible deficiency in one of the essential amino acids, all the enzymes whose "recipe" requires that ingredient cannot be assembled, and thousands of metabolic reactions cannot take place. 

For who ? Construction mission!

Because of their essential component, anyone following a low-calorie diet benefits from this type of supplement. Indeed, EAAs deficiency affects much more than performance in the gym. However, in the interest of improving training, someone on a muscle mass gain will benefit more from EAAs than BCAAs. The synthesis of muscle mass, therefore the construction and character anabolic of the performance goal implies a more comprehensive equation requiring more than the trio of BCAAs. The metabolic reactions involved in "building" muscle mass require the presence of all essential amino acids in sufficient quantities. This is why supplementing with EAAs is more relevant.

Both families of amino acids are meant to be on supplement store shelves, but your personal goal, like your diet and workout protocols, will favor one over the other. Be sure to seek advice from in-store advisors. 

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