GLUTAMINE
The Extreme Anabolic Stimulator:
Glutamine is known to promote anabolic conditions in muscle cells and increase the rate of protein synthesis. It was long thought that glutamine was indirectly responsible for this anabolic state. It now seems that glutamine indirectly promotes growth by increasing the hydration state of muscle cells.
The amount of water in cells can change in a matter of minutes, going from being fully hydrated to a state of dehydration. It has been found that the amount of water inside a muscle cell can alter its metabolism, especially protein synthesis and turnover. When cells are swollen with water, this inhibits the breakdown of protein, glycogen and glucose and stimulates protein and glycogen synthesis. If a cell becomes dehydrated, it shrinks and goes into a catabolic state that breaks down the muscle’s vital proteins.
When glutamine levels are high in muscle cells, this stimulates the entry of other amino acids into the cell. Amino acids cannot directly enter the cell but must be carried in by a special transport system. The unique thing about this system is that when it allows an amino acid to enter, it also allows sodium to enter.
As the amino and sodium levels increase in the cell, this causes water to be absorbed across the membrane and the cell swells to an anabolic state. When glutamine levels are depleted during intense exercise the cells become dehydrated and enter a catabolic state.
When a person trains intensely they will start depleting their muscle glutamine stores before they have fully recovered from their previous workout. The result is that each day the amount of muscle glutamine gets a little lower. The more a person trains, the more glutamine they use and the greater the catabolic response.
People suffering from overtraining are also more susceptible to disease and infection as a result of lowered immunity. This may be due to the role of glutamine as a primary source of fuel for the immune system.
What do they do?
Branched-chain amino acids (BCAAs) include leucine, isoleucine and valine. BCAAs are needed for the maintenance of muscle tissue; they are also needed during times of physical stress and intense exercise. Research shows that BCAA supplements help even those with amyotrophic lateral sclerosis (Lou Gehrig disease) maintain muscle strength (1). In addition, individuals with liver disease (hepatic encephalopathy) benefit from intravenous administration of BCAAs (2).
Where can they be found?
Dairy and red meat contain the greatest amount of BCAAs. They are present in all protein—containing foods. Whey protein and egg protein supplements are other sources of BCAAs. BCAA supplements provide the single amino acids leucine, isoleucine and valine.
Under what conditions might BCAAs be supportive?
BCAAs are sufficient for athletic support and post-surgery recovery.
Who is likely to be deficient?
Periods of physical stress, such as intense weight lifting and long distance running can create a catabolic state in which muscle tissue is broken down. In these situations, supplemental BCAAs—particularly leucine and its derivatives ketoisocaproate (KIC) and hydroxymethylbutyrate (HMB)—can be beneficial in reducing protein breakdown (3, 4). Nonetheless, BCAA supplements may reduce muscle loss and speed muscle gain. BCAAs may also be useful to anyone wanting to prevent muscle breakdown (5, 6, 7).
How much should I take?
A diet including animal protein provides an adequate amount of BCAA for most people. Athletes involved in intense training often take 5 grams of leucine, 4 grams of valine and 2 grams of isoleucine per day to prevent muscle loss and increase muscle gain.
Are there any side effects or interactions?
To Date, side effects have not been reported with the use of BCAAs. A high intake of BCAAs are simply converted into other amino acids or used as energy. It is prudent to take BCAAs along with whole proteins, such as lean meat or poultry and multiple vitamins/minerals, especially the B-complex vitamins.
