What are BCAAs (Branched-Chain Amino Acids)?

The BCAAs are leucine, isoleucine, and valine. The name “branched-chain amino acids” is derived from the structure of these compounds. Each one has a forked outcropping that looks a bit like a branch, hence the name branched chain amino acids..The three BCAAs fall into the category of essential amino acids. Essential amino acids are amino acids that the body cannot synthesize on its own and therefore must get adequate amounts through dietary sources. In fact, even though there are about 20 amino acids that the muscles use for growth, the BCAAs comprise roughly a third of the amino acids within muscle tissue. So if muscle growth is your goal BCAAs are a must.

BCAAs & Metabolism

It may not seem like the metabolic process of different amino acids matters as long as the end point is muscle tissue. The truth is that the manner in which amino acids are metabolized plays a large role in their functions within the body. The metabolism of BCAAs is different that the metabolic processes of other amino acids. What truly makes the BCAAs special is how they are metabolized. While most amino acids are metabolized in the liver, BCAAs are metabolized primarily by muscle. Despite their structural similarities the three branched chain amino acids have different metabolic routes. The breakdown of leucine is accomplished solely through fat pathways. Valine is broken down solely through carbohydrate pathways, and isoleucine through both. The different metabolic pathways of these three amino acids lead to varying requirements for each.

BCAAs, unlike most other amino acids, are metabolized within muscle tissue, allowing them to be oxidized (used as energy) by muscle cells to produce cellular energy in the form of ATP. ATP is the primary source of energy that fuels muscle contraction and allows you to lift weights.

The fact that leucine, isoleucine, and valine are metabolized within muscle tissue allows them to be a quick energy source when the body needs it. There is a significant increase in BCAA metabolism during prolonged exercise simply because the body requires more energy during periods of stress such as training. This makes BCAAs incredibly effective when taken around the time of your workout routine.

BCAAs & Performance

Improving performance during training is of utmost importance no matter what your goals. If you are an athlete, improved performance will help you in your sport of choice during actual competition.

BCAAs have been proven in many studies to be a potent performance enhancer, and as previously mentioned, BCAAs make a great energy source for working muscles because of their unique metabolism. This can have a positive impact on performance. Not only can BCAAs be used as energy themselves but they also enhance fat oxidation in glycogen depleted subjects. This allows individuals to train harder for longer without fatigue due to the higher energy demands being met. This goes for both high intensity training as well as endurance training.

Another way that BCAAs can enhance performance is through their ability to spare glycogen during training. Found as stored carbohydrates within muscle tissue and the liver, glycogen is the favored fuel source for working muscles engaged in high intensity exercise. This makes glycogen availability and preservation vitally important if you wish to continue to train hard for longer periods of time. Studies have shown that by ingesting BCAAs before and during training glycogen levels can be spared by 25%. It is thought that the ingestion of BCAAs boosts blood alanine levels which gets converted to glucose in the liver and then sent back to working muscle to be used as fuel. This glycogen sparing effect of BCAAs will not only allow for more intense training sessions but also allows for faster recovery leading to a better workout tomorrow.

BCAAs effects on Hormones

They are the primary determinant for how much muscle someone will build. They are what separate elite athletes from everyone else, and cause the muscular differences between men and women. They are hormones! The hormones that are of most importance to us are anabolic hormones. Anabolic hormones are hormones within the body that promote protein synthesis (muscle growth), and the most notable anabolic hormones are testosterone, insulin, and growth hormone (GH). These hormones play a large role in controlling your muscle building destiny. Luckily it has been shown that BCAA intake can have a positive effect on anabolic hormone release.

Testosterone may be the most well known of the anabolic hormones. BCAAs can have a positive impact on testosterone levels when consumed pre-training. During intense training it is normal for testosterone levels to rise. After training testosterone levels will begin to fall back to normal baseline levels. Studies have shown that when athletes were given BCAAs prior to training, post-workout testosterone levels remained elevated for several hours, whereas the control groups noticed a significant drop in testosterone once training ceased. This can go a long way to maximizing growth from every single training session.

Ingestion of BCAAs not only increases testosterone in the post-training period but also builds muscle by improving the body’s testosterone to cortisol ratio. While testosterone is an anabolic hormone and promotes muscle growth, cortisol is a catabolic hormone and breaks down muscle tissue. Anyone looking to build muscle will want testosterone levels to remain high while minimizing the release of cortisol. It has recently been found that taking BCAAs while resistance training results in significantly higher testosterone levels with a lower creatine kinase and cortisol response. This leads to more muscle tissue being built and less muscle tissue being broken down.

Lastly, the amino acid leucine has also shown promise for increasing insulin sensitivity. Essentially, insulin sensitivity ensures that the insulin within your body maintains its effectiveness. This leads to easier fat loss, more muscle growth, and defense against diabetes.

BCAAs are a safe and effective way to naturally manipulate hormone levels leading to greater results all around.

BCAAs & Fat Loss

The effects of BCAA intake on fat loss is something that has only been explored in more recent years. Newer research is showing that BCAAs can have a positive effect on fat loss. This doesn’t mean you can eat pizza at every meal with a side of BCAAs and the fat will just melt away though. BCAAs seem to maximize fat loss when one is already on a fat loss diet. On any fat loss diet, carbohydrates will need to be lowered to some degree. It seems that BCAAs ability to spare glycogen and increase insulin sensitivity may play a role in speeding up the results of a fat loss plan.

BCAAs also helps during any fat loss plan because of the muscle preserving effects. On any calorie restricted plan muscle tissue loss is a serious concern that must be addressed. All of the positive effects that BCAAs have on muscle growth will also serve to protect muscle during periods of calorie restriction. It is always important to remember that anything which builds muscle will also preserve muscle.

BCAAs as Signaling Molecules

BCAAs has ability to act as signaling molecules within the body. This has been bringing about some of the most exciting new research in recent years. To get an understanding of how important this is you must first understand the role of protein within the body.

It has long been known that amino acids act as substrate for muscle tissue. This essentially means that when you consume protein, your body will take the amino acids from that protein to compose muscle tissue and other proteins. This is why people often refer to amino acids as building blocks. BCAAs have been proven to be much more than simple building blocks though. Within recent years it has been discovered that BCAAs, particularly leucine, act to send signals to the body that inform it to build muscle.

One of the ways leucine works to signal muscle growth is through it’s interaction with mTOR which stands for mammalian target of rapamycin. The mTOR is located within the cells and, among other things, is responsible for detecting an excess of amino acids. It has been shown to play a key role in regulating muscle hypertrophy (growth). Though this process is not entirely understood, the mTOR pathway has been discovered to be extremely sensitive to the amino acid leucine. Recent tests have shown that when leucine is taken orally it activates mTOR, which activates protein synthesis (muscle growth), and increases a cell’s capacity to produce new proteins (muscle tissue). This means that along with resistance training there is a way to send messages that control growth right at the cellular level. This is truly exciting news.

It is also important to note, although BCAAs can act to signal muscle growth, there must be a full spectrum of amino acids to act as substrate for muscle growth. This means that you can send signals to your body to build muscle all you want, but if it has nothing to build with you are out of luck. So make sure you ingest enough whole protein every day.