Take a look on the back of any protein supplement and it’s almost sure to mention ‘BCAAs’ somewhere. These are ‘branch chained amino acids’, and supplement companies love mentioning them because they make their products sound science-y and potent.
But what actually are these BCAAs? And can they really do you any good?
An Introduction to BCAAs
The purported benefits of BCAAs include:
- Increased lean muscle mass and strength
- Help with fat loss
- Protection of muscle against catabolic processes
Essentially, they do all the things that you want your protein shake to do, and that’s no surprise seeing as they are themselves a type of protein.
As you are probably aware, protein is made up of many ‘amino acids’. These acids provide the ‘building blocks’ of protein as well as muscle tissue and all soft tissue in fact. When we eat protein from meat or from a shake, our body responds by breaking that protein down into amino acids, and then recycling it by using it to heal wounds and build/repair muscle.
Non-essential amino acids are the amino acids that our body can synthesise itself. They are ‘non-essential’ because we already have enough of them in our body. ‘Essential amino acids’ though, are the ones that our body can’t make and thus must be gotten from our diets.
Finally, ‘branched-chain amino acids’ are amino acids that are strung together by branched chains (no surprise there). There are three branched-chain amino acids in total which are leucine, isoleucine and valine. While all three of these are important, leucine is generally considered the most important as it is the most rapidly oxidised and aids with protein synthesis. It is also found in greater abundance in the muscle, and thus most BCAA products will contain a ‘2:1:1 ratio’, meaning that they contain 2 parts leucine to 1 part isoleucine and valine.
And as it happens, these branched chained amino acids are also essential amino acids – they can’t be created in the liver and thus they must be obtained through the diet.
Uses of BCAA Supplements
These amino acids are particularly important for athletes and for our health in general. To give you an idea, these BCAAs make up an impressive 35% of the amino acids found in the muscles, and account for 40% of our daily intake requirements.
Part of the challenge for athletes when it comes to building strength and muscle, is preventing the breakdown of muscle particularly during extensive cardiovascular exercise. Many athletes will thus use BCAAs to try and protect against this breakdown by supplementing with them prior to workouts in the hope that the body will use those instead of getting them from muscle.
For this reason many people will use BCAAs before and during workouts (peri and intra nutrition). This ensures that there is a supply of BCAAs in the blood stream during the workout, and that they will be available for synthesis during the all-important post-workout anabolic window.
Supplementing this way might then prevent muscle breakdown (1) as well as reducing ‘DOMS’ (muscle soreness) (2).
Often BCAA supplements will contain other compounds too. One of these is beta-alanine. Beta alanine is a ‘non-essential’ amino acid as it is produced in the body, but we can still benefit from getting more of it.
The role of beta alanine is, among other things, to increase the amount of carnosine in the muscle. Studies suggest that consuming beta alanine can increase carnosine levels in the muscle by up to 80% (3).
Carnosine meanwhile is a dipeptide produced naturally by the body that is thought to regulate acidity. This may then be able to prevent the burning feeling in muscles that leads to fatigue and failure. As such, increasing the amounts of carnosine available in the muscles has been linked to improved performance on a range of tasks (4).
Taking carnosine directly appears to be less effective as it gets broken down as it passes through the GI tract. However, supplementing with beta alanine appears to increase carnosine and is thus a more effective measure.