The Science Behind Amino Acid Supplements
When you see a product containing amino acids, usually just a few of the 20 different types of amino acids are present. Most often, these products will feature the branched chain amino acids (BCAAs): Leucine, Isoleucine, and Valine.
Research has shown that taking a BCAA supplement immediately before, during, or after resistance training will stimulate protein synthesis and spare muscle breakdown (Sports and Exercise Nutrition, 4th ed.).
A friend of mine asked why amino acid supplements have no calories listed on nutrition facts labels, and I thought that was a great question that warranted an explanation here. The easiest way to think about this is that our body obtains energy through the release of energy stored in chemical bonds.
The energy from carbohydrates, for example, is stored in the bonds between carbon, hydrogen, and oxygen atoms that makes up carbohydrate molecules. However, those individual components, when not chemically bonded to each other to form carbohydrate molecules, contain no energy. Using the same principle, amino acids are building blocks of protein. The picture below illustrates this well:
So, while amino acids are essential for building and repairing muscle tissue in the body, they do not themselves contain energy or calories. If you have any follow-up questions please let me know!