This article was written by Kevin Sprouse, DO, CAQSM. Dr. Sprouse is a team physician for the Cannondale Pro Cycling Team, has a degree in exercise science, and is board-certified in two medical specialties. He practices Sports Medicine at Provision Sports Medicine in Knoxville, TN. Branched Chain Amino Acids (or BCAAs) are something you may have heard of, may think you know what they are, and may even think you know how to use them effectively as a supplement. Or this may be a brand new topic for you. Either way, BCAAs can be a fantastic addition to your diet and training, and we’ll discuss a few interesting ways in which you can utilize them in your daily routine. Previously, there was a great blog post published about BCAAs, what they are, and how amino acids function in the body. If this is an entirely new topic for you, take the time to re-read that article for some foundational knowledge. Very briefly, amino acids are the “building blocks” of proteins in the body. There are 22 different amino acids, nine of which are considered “essential”, meaning your body cannot synthesize them. Of these, leucine, isoleucine, and valine are the “branched chain” amino acids. Leucine is integral to muscle protein synthesis, and isoleucine helps your cells utilize glucose. I’m guessing you are not reading this for a biology lesson though. Let’s talk about ways in which you can use BCAAs to train smarter and perform better! Anti-Catabolic Effect In a person who is training or exercising, there is a constant battle between catabolism (breakdown) and anabolism (rebuilding). The harder you train, the more you breakdown your body. Given the appropriate time to recover and adapt, that is not necessarily a bad thing. The goal of training is to stimulate the body to respond to training stress and build itself to be stronger and better-suited to face that stress again in the future. BCAAs can play an important role in this process. Fasted Training: Many athletes utilize fasted workouts, in which they may engage in lower intensity training after 10-12 hours without food. Such sessions can be very beneficial metabolically for athletes, but they can quickly become a detrimental, catabolic event if not careful. BCAAs have been shown to counteract the muscle breakdown that occurs during such fasted training. The last thing you want to do when training is to sacrifice lean muscle! BCAAs are not a source of calories, so you can ingest them prior to such a workout and remain in a fasted state. Depending on the length of your training session, they are great to use during workout too. You’ll be able to gain the benefits of a fat-burning aerobic training session while minimizing the catabolic effect you would normally encounter. Recovery and Adaptation: Immediately following a workout or race, we are often told that there is a very defined window during which we need to refuel. It can get a little complicated though. You want to begin to replenish glycogen stores quickly, so carbohydrates are a necessity. Protein is recommended as well, because you want to halt any catabolic effect and begin to rebuild. However, if you take the two macronutrients simultaneously, the protein will slow the digestion of the carbohydrate. A simple strategy is to start with a mix of carbs and BCAAs immediately after finishing your training or race. The BCAAs will serve to diminish muscle breakdown while not impeding glycogen replenishment. Once that drink is finished, give it 15-20 minutes to digest. You can then start to replace protein with supplementation or real foods. Decrease Fatigue / Bonk Exercise Fatigue: With extended bouts of exercise, it is not only the body that gets tired. The brain begins to fatigue as well, which directly impacts performance. Have you ever made a dumb mistake late in a race? Yeah…I think we’ve all been there. As you exercise, your body uses the BCAAs which are floating around. As their level drops, another amino acid, tryptophan, is shuttled into the brain. When this happens, serotonin is produced, eventually leading to fatigue. Supplementing with BCAAs during exercise can help to stave off this serotonin-induced fatigue. Bonking: Another experience that all athletes have had is the dreaded “bonk”. (In Europe where “bonking” has an entirely different meaning, this is often called a “hunger flat”.) It was once thought that this occurred solely due to emptying one’s glycogen stores, but there is more to it than that. As I mentioned earlier, BCAAs help your muscles with uptake of glucose. When BCAAs levels drop due to their utilization during exercise, you become less efficient at getting glucose into your cells. Taking a BCAA supplement during exercise can help to delay or prevent “bonking”. Since these studies were published, you may have noticed that many more companies that make gels have started to include BCAAs in their formula. There is a reason for that! Given all of this info, I hope you can see that there is a very good case for making BCAAs a standard part of your nutrition and training regimen! For most athletes, it makes sense to use a reasonable dose of BCAAs before, during, and/or after a training session. Depending on the goal of your workout, you can tailor your use of this supplement to support your effort.