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Calgary, AB / 587-437-3197 / jenna@simplynurtured.ca

2016 by Jenna Lessner 

  • Jenna Lessner, BSc, CHNC

What exactly are BCAAs?!

Updated: Feb 13

Walk into any gym and you’ll witness many people sipping on their BCAAs in between sets. The general thought is that consuming BCAAs during your workout or shortly thereafter will help to increase muscle growth and repair tissue damage from exercise. But what are BCAAs exactly? And do we need to supplement them?

The nutritional supplement industry has become a multi-million dollar industry with a huge variety of products claiming to help every ailment you can think of. Don’t get me wrong there are supplements that some people require due to deficiencies and I give supplement recommendations to many of my clients. However, I also see many people taking supplements that aren’t needed. I believe that a well-rounded whole foods diet should always come first. Supplements should be just that, Supplemental. They are not a replacement for a poor diet. The bioavailability of nutrients in actual food is much higher than the supplement form. Meaning we are better able to absorb nutrients from our diet than a supplement.

BCAA stands for branched-chain amino acids. Amino acids are the building blocks of protein. There are 20 amino acids that comprise muscle protein which 9 of them are considered to be essential amino acids. They are essential because we cannot manufacture them ourselves and they must be obtained through our diet. All 20 amino acids are required for the synthesis of new muscle protein, which occurs on a continuous basis as muscle protein is in a constant state of turnover. Meaning we continuously produce new protein while older proteins are degraded. The process of building new proteins is called muscle protein synthesis. Branched-chain amino acids are 3 of the 9 essential amino acids; leucine, isoleucine and valine.

The wide use of BCAAs is due to a popularly believed claim that the consumption of BCAAs stimulates muscle protein synthesis and results in an anabolic response. There have been claims that the consumption of BCAAs increase muscle mass, improve recovery time and increase strength.

In truth, an abundance of all 9 essential amino acids is required for the significant stimulation of muscle protein synthesis. When only 3 of the essential amino acids are consumed, such as BCAAs, muscle protein breakdown is the only other source of the remaining 6 essential amino acids required for muscle protein synthesis. Meaning it is theoretically impossible for muscle protein synthesis to exceed muscle protein breakdown with the consumption of only BCAAs. The few studies of BCAAs consumption in human subjects have actually shown decreases in muscle protein synthesis, instead of increases as marketed.

Research shows that consuming all essential amino acids of approximately 20-40 grams can maximize muscle protein synthesis. Furthermore, consuming quality complete protein post-exercise increases muscle protein synthesis, supporting an increase in strength and improvements in body composition. Adding carbohydrates to your post-workout meal will replenish muscle glycogen stores and allow you to improve performance. You need to try my Post-Workout Green Smoothie, which provides you with the protein and carbohydrate your body requires after exercise.

Post-Workout Green Smoothie

Serves 2


  • 1/4 cup Protein Powder (vanilla)

  • 2 cups Water (cold)

  • ½ Avocado

  • 1 Banana (frozen)

  • 2 cups Baby Spinach


  1. Add all ingredients into a blender and blend until smooth. Divide into glasses and enjoy!

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