Building muscle requires more than just lifting weights in the gym. It’s a dynamic process that needs the right nutrition, an adequate training stimulus, and enough recovery. Whilst most people tend to train well enough, less emphasis is placed on the vital rest and recovery period.
We’ve compared BCAAs vs glutamine - two popular recovery supplements that may have beneficial applications.
BCAAs vs Glutamine – BCAAs might help to build muscle and prevent muscle protein breakdown especially when dieting if you’re not consuming adequate protein. Glutamine supplementation helps to maintain immunity and gut lining, playing a preventative role in conditions such as irritable bowel syndrome and celiac disease.
What are Amino Acids?
Before we talk about each supplement in more detail, we need to understand more about amino acids.
Amino acids are organic compounds that join together in a sequence to make up the building blocks of protein. Each sequence contains up to 21 different amino acids that can be classified into three groups:
Non-Essential – Six amino acids are considered non-essential. This means that you don’t need to supplement them as your body can produce them.
Conditionally Essential – Another six amino acids are conditionally essential. This means that your body can make them but you may still need to supplement in certain conditions.
Essential – Nine amino acids are considered essential. Your body can’t make these, meaning that you have to get them from food.
BCAAs and glutamine are both isolated amino acids that can be classified in one of these three categories. Let’s take a look in more detail:
What are BCAAs?
BCAAs or branched chain amino acids are considered essential amino acids meaning you need to get them through your diet or as a supplement.
They are comprised of three amino acids which are:
These three amino acids are known as branched because they are the only ones that have a side chain that forms a branch. Out of the three, leucine is thought to have the most important role in muscle building.
BCAAs make up approximately 35-40% of the essential amino acids found in most mammals' bodies. They are metabolized directly in the muscle which is one of the main reasons why they are seen as an important fuel source for muscle processes such as growth and recovery.
When daily protein intake is sufficient, the use of BCAAs isn’t necessary. Compared to whey protein, the use of BCAAs doesn’t provide any added benefits, with overall daily protein intake the most important factor.
What is Glutamine?
Glutamine is a conditionally essential amino acid which means it may be needed by your body in rare instances of disease where your body can’t produce enough.
However, under normal circumstances, your body produces enough to satisfy its requirements as long as overall daily protein targets are met. When supplementing glutamine, up to 90% of it doesn’t reach the bloodstream as most is used in the guy or excreted with urine.
Glutamine is the most abundant amino acid in the human body, accounting for approximately 50-60% of all the amino acids. This is because it’s involved in multiple physiological processes that are needed to maintain normal function.
Alongside helping with protein synthesis, glutamine is thought to have essential roles in our immune system and intestinal health.
It exists in two forms - L-glutamine and D-glutamine. They are very similar but with slightly different molecular structures. L-glutamine is the most important form and also the name used by most supplement brands.
BCAAs vS Glutamine
Whilst both are considered amino acids, the molecular differences between BCAAs and glutamine change their mechanisms and therefore suitable uses. Here are the main differences between glutamine vs BCAAs:Whilst both are considered amino acids, the molecular differences between BCAAs and glutamine change their mechanisms and therefore suitable uses. Here are the main differences between glutamine vs BCAAs:
1. Scientific Backing
According to the International Society of Sports Nutrition (ISSN), supplements are classified into three categories:
- Strong Evidence
- Mixed Evidence
- Little/ No Evidence
Both supplements have a slightly mixed reputation when it comes to the amount of proven benefits shown in scientific literature.
BCAAs have been placed in the mixed evidence category meaning that some studies show benefits whilst others show none at all. BCAAs may be useful in certain situations which I’ll explain below.
Glutamine has been put in the little or no evidence category meaning that it most likely doesn’t have any effects on markers of performance.
BCAAs can be useful in certain situations where overall protein intake isn’t sufficient. If you consume an adequate diet, supplementation probably isn’t needed.
Glutamine can help with immunity and improve gut barrier function so may be used as a preventative supplement for overall health and well-being.
BCAAs vS Glutamine: Summary
Both supplements have slightly mixed reputations when it comes to scientific literature but use of each may be warranted in specific situations.
Pros/Cons of BCAAs
Increased Muscle Protein Synthesis
Decreased Muscle Protein Breakdown
Improved Recovery Markers
Could be improved:
Mixed Scientific Evidence
Pros/Cons of Glutamine
Improve Immune Function
Improved Intestinal Health
Improved Recovery Markers
Could be improved:
Little Scientific Evidence for performance and muscle growth
BCAAs vS Glutamine: When to Use Each
Both BCAAs and glutamine seem to have applications in specific situations. Here’s when you should take each one according to your goals:
1. For Weight Loss
When losing weight, muscle protein breakdown might increase as your body can look for alternative energy sources. It can also increase during chronic infection or illness and as part of the aging process.
BCAAs have been shown to have some effects on the rate of muscle protein breakdown.
It’s important to note that overall protein intake is a much more important factor rather than BCAA intake alone, with a number of added benefits, especially when you’re trying to lose fat on a small calorie deficit and want to keep as much muscle mass as possible 🙂
Glutamine has been shown in some studies to change the composition of your gut microbiome which is important for health and weight management. It may also protect against inflammation and have immunostimulatory effects.
Glutamine improves intestinal health by reinforcing the gut barrier, preventing harmful toxins from passing through. This may help to protect against certain diseases including irritable bowel syndrome, celiac disease, and infectious enterocolitis.
BCAAs may help reduce sarcopenia in older populations whilst glutamine may have weight loss applications by altering the gut microbiome and gut barrier.
2. For Recovery
Improved recovery seems to be where both supplements may offer the most promise, especially if you are dieting or performing multiple exercise sessions in a short period.
BCAAs have been shown to have promising effects on muscle recovery, reducing protein breakdown and the severity of DOMS following supplementation. Supplementing with them may help to speed up recovery time in certain situations.
Supplementing glutamine may help to aspects of recovery through improvement in immunity and gut health.
Both BCAAs and glutamine seem to have some recovery applications during certain situations. For a healthy athlete/person with sufficient protein intake, the use of BCAA and L-Glutamine most likely won’t produce significant outcomes.
Due to the low evidence base, options such as creatine, whey protein, and L-Carnitine L-Tartrate provide better ways to improve performance, muscle growth and promote recovery.
3. For Muscle Gain
One of the most popular uses of BCAAs is to promote muscle gain. Leucine has been shown to activate a pathway that helps with muscle protein synthesis which is the main purported mechanism.
Whilst some research has shown increases in MPS with a BCAA drink, a whey protein shake containing a similar amount of BCAAs seems to be far superior in studies suggesting a protein source with a full amino acid profile is the better option.
Glutamine helps with protein synthesis but supplementation has been shown to have no effect on muscle mass when compared to a placebo.
BCAAs may help if you can’t consume a complete protein source regularly such as when you’re dieting or heavily exercising but offer little benefits on top of this.
The Transparent Labs BCAA Glutamine powder is formulated using a 2:1:1 ratio of leucine, isoleucine, and valine. On top of this, it contains L-glutamine and coconut water extract to give you a versatile supplement that helps support muscle protein synthesis and reduce muscle fatigue.
Photo by @transparentlabs
Transparent labs have sweetened the BCAA Glutamine powder with stevia and included a full ingredient breakdown on the label. It’s free from artificial colorings and preservatives and comes in four flavors.
The Cellucor Glutamine powder uses COR-Performance glutamine that helps to lower your stress levels and reduce muscle protein breakdown following a bout of exercise.
Each 5-gram serving contains zero calories making it perfect to add to your post-workout shake if you are looking for a clean source of glutamine that can help with recovery. It offers excellent value for money, with 72 servings in each container.
Which is better, glutamine or BCAAs?
BCAAs and glutamine may have applications in certain situations as discussed above but aren’t needed if a good diet is consumed. Which one is a better supplement depends on your diet and training goals.
Should I take glutamine and BCAAs?
The best supplement to take out of BCAAs and glutamine depends on your overall workout goals and general lifestyle.
Supplementing with BCAAs can help with recovery and DOMS, when daily protein intake is insufficient. If you are vegetarian or vegan, usage may be warranted. Glutamine can help with overall immunity and gut health. Both can also be taken together.
Is it better to take glutamine or BCAAs after a workout?
Following an intense workout, the use of a BCAA supplement may be warranted to help with delayed onset muscle soreness when overall daily protein intake isn’t sufficient. BCAAs work best tho when taken with other EAAs.
BCAAs can be taken during and after a workout, with possible applications in helping with muscle building and repair. BCAAs may only be useful in certain situations such as a dieting phase or for ultra-endurance athletes to drink alongside carbohydrates and electrolytes.
Glutamine would be the better option post workout but both can be taken together if desired.
Amino acids are the building blocks of protein that are essential for muscle growth and repair. BCAAs and glutamine and both amino acids with different roles in muscle recovery and health.
When considering if to take l glutamine or BCAAs, both supplements seem to have some uses. Glutamine may be warranted for immunity and gut health when you are sick whilst BCAAs may provide benefits for vegetarian/vegan athletes when deficient or ultra-endurance athletes during workout.
Both lack major scientific backing for most alleged benefits, with more research needed to prove the functional applications for athletes.
Have you taken BCAAs or l glutamine before? What about BCAAs and glutamine together? Let me know about your experiences below!
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