Branched-chain amino acids, otherwise known as BCAAs (which include leucine, isoleucine and valine), are generally used by endurance athletes as an alternate source of energy when glycogen (carbohydrates stored as energy in the muscles) reserves dip too low (Rosenbloom). BCAAs are highly coveted among athletes because they have a much greater impact on muscle protein synthesis; they are also responsible for muscle recovery, muscle energy and preservation of lean muscle mass. BCAAs are the first amino acids to be pulled from the muscles as a source of energy. Without an adequate and consistent supply of BCAAs, muscles can and will become depleted from exercises specifically meant to strengthen them. Of the three BCAAs, leucine is the only amino acid with the ability to stimulate muscle protein synthesis and is the most abundant BCAA, making leucine extremely unique. Not only does leucine build muscle, it also facilitates the absorption of glycogen into the muscles, increases fat loss through muscle-sparing and helps to stabilize blood glucose levels. No wonder it has become one of the top selling dietary supplements! However, “current evidence indicates that protein and amino acid supplements are no more or less effective than food when energy is adequate for gaining lean body mass” (ADA 522). And, they “are a potential source for illegal substances such as nandrolone, which may not be listed on the ingredient list” (ADA 522). Therefore, take caution if you decide to use these types of supplements.
The best way to consume an adequate amount of protein (and thus, amino acids) is to stick with whole foods naturally rich in BCAAs such as meat, fish, poultry, eggs and. A prime example and perfect post-workout beverage is low-fat milk. Stay tuned for the next segment on why milk actually “does a body good!”
Choosing A High Quality Supplement
Because the FDA does not regulate supplements it is important to select supplements that are approved by a third party for quality, purity and disintegration. Look for one of the four following certifications: CL (Consumer Labs) and USP (The United States Pharmacopeia) or if you are an athlete, NSF and Informed-Choice marks. These marks must be present on the supplement bottle to ensure that they have been tested and approved. To see which supplements carry a certification visit their respective websites.