Glutamine is an amino acid involved in several physiologic processes including nucleotide synthesis and ammonia detox. Because of the key roles glutamine plays in the body, it’s been researched for its effects on general health and athletic performance. We know supplementing with the amino acid can quickly replenish glutamine levels following a tough workout and it aids the recovery process. 

Scientists wanted to see if they could enhance glutamine’s bioavailability by utilizing a novel microencapsulation technology. They conducted a pilot study to test their hypothesis out, and we were simply blown away by the results. 


Microencapsulated Glutamine Pilot Study

A randomized, double-blind, crossover design clinical study was done on 8 male subjects to determine the time-release effect of microencapsulated glutamine in athletes and the availability of plasma glutamine after supplementation.  Participants were randomly assigned to a placebo (free form glutamine) group and a microencapsulated glutamine group, and then “crossed over” to use the other type. Neither the subjects nor the researchers knew who was consuming which form of glutamine while they were being tested.

The subjects in the study were physically active and performed physical activity lasting at least 45 minutes on five or more days each week. The time-release glutamine used in the study was microencapsulated in a vegetable protein matrix with a ratio of 90:10 L-Glutamine:vegetable protein.

Following an intense session of resistance training, subjects supplemented with one of the following:

  • (Placebo group) 5 g. standard L-Glutamine every 4 hours for a total of 20 g free form L-Glutamine daily
  • (Experimental Group) 5 g. Microencapsulated Glutamine every 4 hours for a total of 20 g Microencapsulated L-Glutamine daily

Researchers collected relevant markers including biopsies, blood samples, and saliva samples of the study subjects.

Microencapsulated Glutamine showed significantly enhanced plasma bioavailability compared to free form L-Glutamine. Researchers measure the fractional synthetic rate (FSR) of myofibrillar proteins to observe how much of a precursor compound, in this case, a tracer amino acid, is incorporated into the myofibrils (muscle cells). It serves as a good marker for physiologists to observe how much muscle synthesis (or breakdown) is occurring. Myofibrillar FSR significantly increased 15 days after the consumption of Microencapsulated Glutamine. And Microencapsulated Glutamine relative to free form L-Glutamine showed significant increases in MPS for a minimum of 24 hours after ingestion.[1]



To recap, the pilot study showed that after consistent supplementation with glutamine researchers were able to observe significantly elevated levels of plasma glutamine compared to standard glutamine. After 24 hours, muscle protein synthesis was elevated in the microencapsulated group. This is an important feature because when the rate of muscle protein synthesis exceeds that of muscle protein breakdown, the body is in a net positive protein balance which is a more favorable state for muscle growth to occur. And finally, after 15 days the myofibrillar fractional synthetic rate was increased in the microencapsulated glutamine group. While the researchers didn’t measure for increases in muscle mass in this pilot study, the observed increases in these factors all lend themselves over time to an environment that favors increased muscle mass. Future research will explore this exciting possibility.


To replicate the pilot study conditions that showed a significant increase in absorption and protein synthesis, it’s recommended that you take a total of 20 g a day of Microencapsulated Glutamine, split into four 5 g servings every 4-5 hours.


Microencapsulated Glutamine stacks especially well with citrulline as an arginine precursor to support increased pumps [2], with Amino Synergy to support increased muscle protein synthesis, with CreaClear for a super absorbing anabolic stack and with Hydra-Charge for effective hydration support.


[1] Michelle Hone et al, 2019.. “Microencapsulation of L-Glutamine and its effects on bioavailability.” pilot study.

[2] Ligthart-Melis, G C, and N E P Deutz. “Is glutamine still an important precursor of citrulline?.” American journal of physiology. Endocrinology and metabolism vol. 301,2 (2011): E264-6. doi:10.1152/ajpendo.00223.2011

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