Bodybuilding Fitness

Branched chain amino acids – from bodybuilding to weight loss

By Kim Crawford, M.D. Last updated: February 7, 2018
uses branched chain amino acids

Branched chain amino acids are a must for muscles and more!

uses branched chain amino acidsBranched chain amino acids (BCAAs) are a direct source of energy for skeletal muscles.

At the same time, they are ATP-producing via the citric acid cellular energy cycle.

In addition, they influence how much lean muscle mass you have. They stimulate the building of protein in muscle, help reduce muscle breakdown during exercise and regulate protein metabolism throughout the body. Read on to unveil the life changing benefits of branched chain amino acids.

The Basics of Branched chain amino acids:

The branched chain amino acids (BCAAs) are made up of three essential amino acids. This includes leucine, isoleucine, and valine. BCAAs make up 40 percent of the daily requirement of all nine essential amino acids. Does that show you how important they are? BCAAs are in foods containing protein, with the highest concentrations in eggs (specifically the whites) and whey protein. Chicken, beef, and salmon contain respectable amounts too.

Branched chain amino acids can also be supplemented. This means faster pre-workout delivery to the bloodstream for all athletes including those who use them the most, bodybuilders. Why? Free form BCAAs bypass the liver and gut to go directly into the blood stream.

The more BCAAs that are present in the muscles, the more they will be of use for energy, slowing the breakdown of muscles cells and preventing muscle loss. Here’s a “fun fact”: If you are using nutritional ketosis for weight loss or health, ketones “spare” branched chain aminos. This means that you can utilize a healthy ketotic diet interspersed with your workouts and not have any fear of muscle mass loss. For details, please see the referenced article.

Some Fun Facts before the Details:

BCAAs trigger protein synthesis in muscles and inhibit the breakdown of muscle cells. They increase energy production during exercise, so people use BCAAs during workouts. They reduce muscle soreness from intense muscle-damaging exercise.

People who consume essential amino acids that contain BCAAs with every meal have less visceral belly fat and more lean body mass. In healthy people, BCAAs improve glucose uptake and insulin sensitivity. In diabetics, BCAA dietary intake with other therapeutic interventions may improve disease control and disease markers. BCAAs convey many health benefits, and a higher dietary intake has been identified as a predictor of longevity.

BCAAs Enhance Muscle Protein Synthesis:

Branched chain amino acids trigger protein synthesis. When you combine BCAAs with resistance exercise, you get maximal protein synthesis. Combining these trigger what is called the mTORC1 signaling pathway that is crucial to build muscle.

Muscle tissue takes BCAAs along with l-glutamine and, to a lesser extent, l-alanine and l-aspartate for energy. Muscles burn BCAAs for energy during exercise, making a large pool of branched chain amino acids essential for performance.




Branched chain amino acids also help if you have to take time off from training. Indeed, increasing your BCAA intake will minimize muscle loss.

Also, because branched chain amino acids trigger protein synthesis even without exercise, lean muscle tissue is preserved to then keep up metabolism and help prevent fat gain.

BCAAs May Improve Strength Development With Training:

A recent large-scale analysis of training studies showed that protein supplementation led to much greater increases in leg press strength. This review included a variety of protein sources with high branched chain amino acid content.

A study of untrained young men taking 4 grams per day of the “main” branched chain amino acid, leucine, showed remarkable results. After 3 months of weight training, the “leucine group” gained significantly more strength than the control group who received a placebo.

The leucine group increased strength by an average of 31 percent more on all exercises compared to the placebo group. This study hasn’t been replicated with branched chain amino acid supplementation. Indeed, high BCAA-protein supplementation has been found to lead to greater strength development when paired with strength training.

This evidence all suggests a diet rich in amino acids from multiple sources including eggs, whey protein powders, meat and branched chain amino acid supplements will maximize strength as well as size results.

BCAAs Enhance Endurance Performance and Decrease Fatigue:

Branched chain amino acids perform quite impressively to enhance endurance. There are various ways BCAAs manage this. First, the body burns BCAAs as energy to maintain ATP energy levels during glycogen-depleting exercise. Branched chain amino acids may also enhance the body’s ability to burn fat which then increases the accessible energy pool. Second, supplemental BCAAs prevent brain fatigue acting as brain boosting supplements.

Tryptophan is the amino acid necessary to make the calming brain chemical serotonin. Tryptophan is blocked from entering the brain, thus reducing “mental fatigue.” Many scientists who study the limits of human performance believe the real limiting factor in performance is when the brain tells you “I’m done.” In one well-done study,  participants who took 300 mg/day of branched chain amino acids for 3 days and then completed in a full-out exhausting exercise trial had 17.2 percent greater resistance to fatigue compared to a placebo.

BCAAs Prevent Muscle Loss During Long-Duration Exercise:

Branched chained amino acids also prevent muscle loss during ultra-endurance exercise. Studies suggest that providing nutritional support with BCAAs or high-BCAA containing protein will prevent catabolism by improving the overall energy-burning pool so that amino acids aren’t released from muscle tissue. In another comprehensive study, trained athletes who performed a 24-hour-long grueling exercise trial experienced significant muscle protein degradation. On biopsy and lab testing, they had evidence of metabolic stress and muscle damage. There was a marked drop in blood levels of BCAAs over the exercise trial as well. The bottom line is BCAAs help with endurance efforts for certain.

BCAAs Decrease Muscle Soreness & DOMS:

BCAAs preserve the integrity of muscle fibers and reduce post-workout soreness. This allows you to train at a higher intensity more frequently. A study of athletically trained men found that dosing BCAAs before and after doing 100 muscle-damaging drop jumps significantly reduced muscle soreness. Maximal strength was decreased 33 percent less than a placebo. The dosing protocol had trainees take BCCA’s for 7 days before and 2 days after training as well as 20 grams before and after the workout for a total of 280 grams. Researchers point to the steady stream of BCAAs as what made them so effective.

BCAAs Support Hormone Balance During Intense Training:

BCAAs support the balance of hormones, which plays a role in an athlete’s ability to respond to advanced training loads.

Another well-done study looked at the effect of loading BCAAs with six grams of BCCAs daily for 3 weeks followed by a week of high-intensity resistance training. Compared to a placebo group, the BCAA group had higher testosterone and lower cortisol. This is where you want to be if you are a bodybuilder; in the anabolic zone—not catabolic zone. One of the dangers of high cortisol, common in bodybuilders, is the subtle loss of muscle mass. Interestingly enough, the BCAA group had lower bio-markers of inflammation. To explain, this indicates they were responding to the training load more effectively.

BCAAs Increase Fat Burning to Support Fat Loss:

Takes BCAA'sSurveys show that people with a higher BCAA intake in their diets have less body fat, more muscle, and better body composition.

A very large study of 4,429 subjects found those with higher BCAA intake were the slimmest and had significantly less chance of being overweight compared to those with lower BCAA intake.

In a review of the role that essential amino acids play in body composition, researchers wrote that the BCAAs have unique obesity-reducing effects.

The uniqueness is on a genetic level. They actually decrease food intake and body weight by increasing the gene signaling of muscle building pathways.

BCAAs May Reduce Diabetes Risk:

The trio of BCAAs can improve insulin sensitivity and metabolic rate for improved body composition in non-diabetics. By keeping fat mass down and lean mass up you lower your risk of developing diabetes. In one recent study, individuals of a weight loss trial who lost the most weight had the greatest improvements in insulin sensitivity and the highest BCAA levels. Please note that diabetics have dysfunctional BCAA metabolism. For them, taking BCAAs elevates insulin, so they are not a treatment for diabetes.

BCAAs Correlate With Longevity and Are Therapeutic:

I love “anything” that can increase longevity. BCAAs have an anti-aging effect because they increase the formation of new mitochondria which is where energy (ATP) is made. In recent studies, BCAAs have been found to extend lifespan in the same way caloric restriction, and intermittent fasting does.

Dosing, ratios, and source of BCAAs:

Recall BCAAs are a collection of three amino acids with a side chain that is branched. They are leucine, isoleucine, and valine (usually in a 2:1:1 ratio in supplements if done correctly). Naturally, it would make sense for athletes to take BCAAs. However, your needs depend more on how much protein you’re eating during the day. It also depends just exactly where you are in the bodybuilding cycle, and it matters if you are a competitive athlete. If you are an endurance athlete, where you are in your training and competition cycle are important factors as well.

If you are a fitness lover and want to be lean and mean, then you’ll just take a dose before workouts. Your muscles need and want BCAAs for growth or holding onto muscle when losing weight. How you receive your BCAAs—from foods, protein powders, or straight BCAA powder supplements—is ultimately up to your preference, bank account and “athletic seriousness” if that is a term.

Most, if not all, serious bodybuilders know whey protein is the most efficient way to take in protein calories. They just add a serving of BCAAs to their whey concentrate shakes. If you are consuming sufficient BCAAs in your diet, you might not need to supplement. However, for a professional bodybuilder trying to “shred” or someone trying to drop fat, supplementation is a good idea.


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