It’s possible that glutamine is the most important amino acid for body builders, but BCAAs also play an important role in muscle growth.

Glutamine vs BCAA: Which is Better For Muscle Gain?

If your goal is to build muscle, no doubt you’re spending time at the gym regularly, lifting weights like a rockstar! However, here’s something you need to remember: a rockin’ body is only made 30% at the gym, and 70% in the kitchen. What you eat and the supplements you take are going to make a huge impact on your gains.

The BCAA and Glutamine Difference

That’s right, you can workout as much as you want, but the food you eat plays a HUGE role in not only your health, but also in your ability to build muscle mass. If you’re not giving your body the right nutrients through food and supplements, it won’t have what it needs to increase muscle fiber size and storage capacity.

BCAAs and glutamine are two of the most popular supplements for packing on muscle mass, but do you know which is better?

What are BCAAS?​

Branch-chain amino acids (BCAAs) are three of the amino acids that your body cannot produce itself, called the essential amino acids, meaning they must come from the food you eat. They play a HUGE role in muscle-building. The BCAAs are:

  • Valine
  • Leucine
  • Isoleucine

Together, these three amino acids make up 33% of the protein your body uses to build muscle.

Not only is muscle made of BCAAs, leucine activates pathways that stimulate muscle synthesis after exercise. Studies have found that drinking BCAAs after strength training can lead to a 22% increase in muscle synthesis.

Whey protein is rich in BCAAs. A 2012 study compared the effect of drinking a BCAA beverage or whey protein (rich in BCAAs and other amino acids) after exercise. They found that whey was 50% more effective in building new muscle than just the BCAAs alone. That is likely because BCAAs are not the only amino acids needed for muscle synthesis.

What is Glutamine?

Glutamine is one of the amino acids that your body is able to produce on its own, called a non-essential amino acid. It is the single most common amino acid in your body. Up to 61% of your skeletal muscle is made from glutamine. It serves as the primary transporter of nitrogen, needed for muscle growth, into your muscles.

Glutamine is depleted with physical activity. The harder you workout, the more glutamine is used up. It can take a week after a workout for the levels of glutamine in your muscles to restore themselves to their original levels. A lack of glutamine, if you are not getting enough protein can lead to increased muscle soreness and pain.

What Role Do Glutamine or BCAAs Play in Muscle Health?

BCAAs are very important for your overall bodily function, but they are SUPREMELY important for muscle growth. As we already mentioned, leucine is needed to activate the muscle building pathway. But, BCAAs do way more for muscle growth!

To begin with, they transport nitrogen into your muscles, giving your body the nutrients it needs to promote anabolic muscle action (growth).

BCAAs also help your body produce more insulin, which allows your muscles to absorb and use the glucose in your blood. They work to produce muscle growth, but they also PREVENT muscle catabolism (breakdown). They help your body to release important hormones like testosterone, GH, and IGF-1, all of which are necessary for muscle growth.

Here are some additional benefits of BCAAs for muscle growth:

  • Taking BCAAs promotes a period of anabolism longer than the catabolism period, leading to muscle growth rather than muscle loss.
  • BCAAs help to fuel your body with free-circulating amino acids, which the muscles can easily absorb to enhance muscular function.
  • BCAAs can help to increase endurance levels, thanks to the fact that they contribute to the enhanced size and energy storage capacity of muscle fibers.

Glutamine, on the other hand, plays a bigger role in the body, beyond muscle synthesis. Not only does it help your body to absorb and metabolize protein, but it also helps to boost your immune function.

It stops muscle catabolism (breakdown), and increases your body’s ability to secrete growth hormone–the hormone that metabolizes fat and supports the growth of new muscle tissue. Taking just a couple of grams of the supplement per day can cause up to a 400% increase in growth hormone production.

Glutamine ensures that you can burn fat WITHOUT losing muscle mass, a common problem among those who exclusively do cardio. Many people trying to lose weight and burn fat fail to do sufficient weight training, which leads to muscle loss as well as fat burning. This ends up slowing your metabolism down to a crawl, making it difficult to keep weight off. Thanks to glutamine, you can prevent this from happening!

Glutamine also promotes a positive nitrogen balance, which leads to muscle growth.

Here are some of the benefits of glutamine for muscle growth:

  • Glutamine is directly connected to the synthesis of protein in your body.
  • Glutamine speeds up the healing process–both post-workout and after an injury–thanks to its ability to maintain cell hydration and volume.
  • Glutamine increases the production of growth hormones, the vital ingredient that contributes to muscle growth and strength increases.
  • Glutamine also helps to boost your immune system, reducing the risk that sickness will take you away from your daily workouts.
  • Glutamine helps to repair damage to your intestines and digestive system, ensuring MAXIMUM absorption and use of important nutrients.

It’s possible that glutamine is the most important amino acid for body builders, but BCAAs also play an important role in muscle growth.

So, Glutamine vs BCAA? Which is better?

Glutamine or BCAA? There is no definitive answer to this question, though many people give glutamine the edge due to its ability to support healthy digestion and immunity. The truth is that both glutamine and BCAAs can help to enhance your efforts to build size and strength, so supplementing with BOTH supplements may be the way to go! Why settle for one when glutamine and BCAA together pack more punch?

BCAAs will help you to build more muscle mass more quickly, and glutamine will help you to recover after those hardcore workouts.

How To Supplement with BCAAs and Glutamine

The best time to take BCAAs is both before AND after a workout. You should take a supplement between 30 to 60 minutes before working out, and take another one within the same timeframe after completing the workout. This ensures that your body has the maximum amount of BCAAs to help you power through that workout, and replaces lost amino acids once you’ve finished working out.

If this seems overwhelming, you can always mix up a BCAA powder and sip it during your workout. It’s always best to take these BCAAs alone, as that will ensure optimum absorption of these three vital amino acids.

When taking glutamine supplement, there are three times to take it:

  • First thing in the morning
  • Immediately after a workout
  • Before bed

This will ensure your body is filled with this amino acid throughout the day, and gives you what you need to repair your body after a long day and a hard workout.

If you don’t want to take two different supplements to get the benefits of glutamine and BCAAs, consider simply taking a whey supplement instead. Whey contains all three BCAAs and a hefty dose of glutamine to support muscle synthesis after a workout. If you need additional support for your immune system or digestion, you can always add a glutamine to your routine for a little boost.




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Kade Brittain