Written by Ben Carlisle
Last updated on: Sep 18, 2022
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Glutamine and Branched Chain Amino Acids (BCAAs) are 2 great supplements to help you get the most out of your workouts. But what is the difference between them, and can they be used together? This article explains everything that you need to know.
Glutamine is an amino acid which helps with recovery, reduces fatigue, aids immune functionality, and supports intestinal health. BCAAs can also reduce fatigue but help with muscle preservation, recovery, growth, and cognitive function. They can be taken together.
To understand how glutamine and BCAAs can improve your exercise performance, you need to understand what they do to your body, which functions they help fulfil, and why they can be used together. Read on to learn about Glutamine and BCAAs...
Glutamine is the most abundant amino acid found in the human body. It is created in the muscles and is carried through blood cells to support different organs (1). Glutamine can exist in two different molecular arrangements (L-Glutamine and D-Glutamine). It is a building block for creating protein, other amino acids, and glucose (1). The “L” in L-Glutamine stands for “left,” and it is a mirror image of the Dextro (“right”) or D-Glutamine. Glutamine will exist in different ratios for your body’s right and left sides.
L-Glutamine is found in food and supplements. L-Glutamine is also considered to be more useful for the body (1). This is the form of glutamine which will be referred to in this article.
Glutamine provides a range of benefits which range from recovery from exercise, reduced fatigue and supporting improvements in general health.
Glutamine supplementation can aid recovery by reducing plasma glutamine levels after a workout. Though not required, supplements can help keep levels normal. The benefit of reducing plasma glutamine levels is it prevents overtraining and improves post-exercise glycogen synthesis, which helps recovery (2).
Research has found glutamine supplementation resulted in significantly lower aspartate transaminase, creatine kinase, and myoglobin levels in the blood (3). This suggests individuals who take glutamine suffer less muscle damage than those who don't. Also in the study those who took glutamine supplementation did not experience an increase in their circulating cortisol levels. This indicates glutamine could help attenuate exercise-induced muscle damage in sport disciplines with predominantly eccentric actions (3).
Another study found glutamine reduced 2 markers of muscle damage; creatine kinase and and lactate dehydrogenase. This would make gluatmine particularly helpful for athletes who practice exhaustive exercises or for prolonged periods. It has also been found l-glutamine catalyzed faster recovery of peak torque and diminished muscles in the aftermath of eccentric exercise. But the effects appear to be more pronounced in men than women (4).
Glutamine supplementation has shown signs of increased muscle glycogen synthesis, which reduces exercise-induced ammonia accumulation, particularly after being administered for more than five days (5).
However, it has also been demonstrated that glutamine supplementation could have limited effects on physical performance, despite the clear signs of improvements to fatigue markers (5).
Pre-exercise glutamine supplementation has also been shown to enhance immune system functionality and defensive inflammatory reactions (6).
Glutamine also shows promising signs of protecting the gut from atrophy and stress-induced injury in mammals and other animals (7). It can also improve gut barrier functions in experimental conditions of injury and other clinical situations (7, 8).
Glutamine is not one of the nine essential amino acids, although sometimes referred to as a “semi-essential” amino acid. In other words, our bodies can produce it at times, but also our diets’ composition of glutamine may not be adequate to fulfil our requirements.
These conditions where glutamine takes on the appearance of essential amino acids are brought about by states of different dietary needs, which can be induced by illness, injury, pregnancy, lactation, and growth. Therefore, glutamine supplementation is recommended for people in these states.
There is also evidence that supports the notion that glutamine is a nutritionally essential amino acid for adults (9).
Branched Chain Amino Acids (BCAAs) are three different essential amino acids that can assist with exercise performance and muscle mass growth. Three amino acids make up BCAAs, namely leucine, isoleucine, and valine.
Leucine is the BCAA which stimulates muscle protein synthesis while directing your body to burn fat for fuel on low-calorie diets. However, it isn’t a precursor for the synthesis of protein. Rather it aids in signalling. Leucine may also initiate an anabolic response when taking with protein (this can be through supplementation or diet). This further aids the synthesis of protein and helps to prevent muscle breakdown. Whilst also burning fat.
Isoleucine also plays a role in muscle protein synthesis, aiding with the ingestion of leucine acids and activating metabolic pathways that oxidize BCAAs, while assisting with recovery.
Valine is released via pyruvate – the output of the metabolism of glucose known as glycolysis. It can also boost energy and muscle repair.
BCAAs can assist with your exercise performance in various ways. Let’s take a look at some of these benefits in detail:
It has been shown that BCAA supplementation has led to less soreness, according to individuals that participated in a study on the effects of BCAAs on recovery following acute eccentric exercise (10).
The oral intake of BCAA supplements can also reduce central fatigue and brain 5-HT synthesis which delays fatigue, allowing individuals to exercise for longer periods. (11).
The intake of BCAA-based supplements available on the market has also been found to be able to improve the serum tryptophan, which leads to a reduced rate of perceived exertion (RPE) and increased Training Impulse (TRIMP) and Time to Exhaustion (TTE) (12).
BCAAs, and leucine, in particular, have anabolic effects on the metabolism, which increases the rate of protein synthesis, which preserves muscle mass through changes to signalling pathways (13).
BCAAs are also useful as a supplement for muscle recovery and immune regulation. It decreases exercise-induced muscle damage and promotes the synthesis of protein while delaying onset muscle soreness, which occurs a day or two after physical activity and can inhibit performance (14).
The anabolic effects of BCAAs and increased rate of protein synthesis have also been found to decrease muscle degradation in resting muscles while having positive effects on myofibrillar protein synthesis (13, 15) .
This means that BCAAs will support musclal hypertrophy, particularly when supplementation accompanies the ingestion of complete protein supplements, such as whey protein (15).
BCAAA Supplementation has also improved cognitive functionality during the late stages of endurance sports while decreasing mental fatigue and perceived exertion. In some circumstances, it has also been found to improve physical performance (11).
In terms of muscle gain, BCAA has the advantage over Glutamine because BCAAs enhance muscle protein synthesis and anabolic effects on protein metabolism (13, 15).
However, research into the effects of Glutamine supplementation has found that subjects taking oral supplements showed no difference in muscle growth compared to placebo groups and no significant effect on muscle performance, body composition, or muscle protein degradation in young adults (16, 17).
Yes, BCAAs and Glutamine can be used together. BCAAs are helpful for muscle growth and recovery, while Glutamine benefits immune system functionality, intestinal health, reduces fatigue, and assists with recovery.
Taking both supplements together can be incredibly helpful for those looking to make gains in muscle mass while receiving enhancements to immune system functions and shorter recovery periods.
So, suppose you’re looking for a good combination of supplements with broad benefits for various bodily functions involved in exercise regimens, particularly muscle growth, recovery, focus, and immune system functions. In that case, a combination of BCAAs and Glutamine may be incredibly helpful.