Glutamine

By Xavier Fox

You are getting started on your journey as a competitive bodybuilder. You have done a little research by reading magazine articles, talking to competitive lifters at the gym you joined, and scanning various websites, but you are still having trouble digesting all of the information that is out there, especially when it comes to supplements. There are so many different types of supplements, and many of them are available in different forms. There are also many opinions on which supplements work, and which ones do not. When it comes to choosing which supplements to spend your hard-earned cash on, there is one multi-purpose supplement that stands out as a smart choice from almost every person you talk to. Whether it is adding quality muscle, keeping your general health at optimal levels, or even increasing energy levels, glutamine can help you create that physique that you have always desired.

Glutamine is a glucose creating (glucongenic) amino acid that performs many functions in your system. Glutamine is normally categorized as a nonessential amino acid. In certain instances though, it is deemed to be “conditionally” essential. If you recall from earlier BodyFitness article on amino acids, “nonessential” does not mean that your body does not need it, it means that your body can produce it from other amino acids. However, do not let that fool you into thinking that your system will produce all of the glutamine it needs on its own. The proteins in your system get used for thousands of functions, and they are not always available for conversion to glutamine, especially when muscle tissue is being broken down at an accelerated rate because of intense resistance training.
When you are lifting weights, your body is actually breaking down muscle tissue. Thousands of micro-tears are created, and these tears are not much different from an injury. When this process occurs, glutamine is depleted from inside the muscle, and then your body will use branched chained amino acids within the muscles to regenerate glutamine. However, as the workout goes on, and your system is continuously breaking down stored amino acids, muscle tissue, and other intramuscular amino acids, the amount of amino acids that are available for manufacturing new glutamine continues to drop. It is not long before glutamine levels are depleted to the point that it could take many hours to replenish them. The body’s ability to manufacture glutamine cannot keep up with the demand. During these hours you are missing out on a lot of potential growth.
A deficiency in glutamine not only hurts the skeletal muscles that you use for lifting heavy weights, but other parts of the body are also at risk for losing capacity to function properly. The kidneys will not be able to maintain acid balance in the body. The liver will not be able to manufacture glycogen effectively, which compounds your problems, because that leads to further muscle tissue breakdown, because muscle will be sacrificed to replenish glycogen stores. Your immune system will suffer, and protein synthesis will decrease. The importance of glutamine in your body cannot be overstated, and allowing glutamine levels to deplete will cause almost your entire system to go haywire.
Since glutamine is an amino acid that is created from broken down proteins, not many people associate it with glycogen replenishment but studies have shown that glutamine is effective in glycogen storage. One of the more popular studies (by Bowtell et al., in 1999) took seven male athletes using both type I and type II fibres to exhaustion to ensure that all muscle glycogen stores were depleted. When the workouts were completed, each male was given one of three drinks post-exercise: 330ml glucose-polymer solution, 330ml glucose-polymer solution with 8g glutamine, or 330ml placebo with 8g glutamine. During the next two hours at evenly spaced times, they had their plasma glutamine levels checked. Two things were noted: 1) As expected, plasma glutamine concentrations were highest post-exercise in the subjects that ingested glutamine containing drinks; 2) Oral glutamine supplementation, without being added to a glucose-polymer, promoted glycogen storage similar to that of the glucose-polymer drink. This shows glutamine promotes glycogen synthesis.
Many detractors of glutamine used to like to argue that about half of the glutamine that you ingest as a supplement is lost during the digestion process. This actually makes sense when you look at how your body uses glutamine. As mentioned earlier, the kidneys use glutamine to maintain acid balance in the body, and many acids are manufactured during weight training due to energy and muscle breakdown and synthesis. The liver uses glutamine to help synthesize glycogen and the small intestine uses glutamine as a source of fuel for enterocytes, which are the cells that line the inside of the small intestines. Your body uses glutamine to keep your intestine and digestive system healthy. So the high level of glutamine not getting into your blood is not the result of it being a poor supplement with poor bioavailability, it is due to it being important to many other important functions within your body. Of course, as your body is put under stress (from lifting heavy weights), the demand for glutamine by the liver, intestine, and kidneys will increase, so much higher quantities will be required by your body to maintain performance levels.
Let’s go back to how glutamine keeps your intestines and digestive system healthy… Glutamine plays a very important role in the gastrointestinal system and its ability to perform. You may be saying, “Yeah, that’s nice… but why is it important enough to buy glutamine?” Well, I’m glad you asked. The gastrointestinal system is made up of your intestines, and they govern your ability to digest food. If your intestines are not functioning properly, then you will not absorb nutrients correctly. The result is that you are not only missing out on your full potential to grow muscle, but you your body will also break down muscle if nutrients are not made available. In addition, you will have a hard time gauging exactly what you should eat, because your system is not digesting food in a consistent manner.
The glutamine that your organs are not using goes straight to making you a weight lifting super hero. One of the best ways that glutamine does this is by its anti-catabolic characteristics. Intense weight lifting is a major stress on your body, and every time your body experiences stress, it releases a hormone known as cortisol. Well, cortisol is probably the worst thing your body can make, because it breaks down muscle tissue and that’s a bad thing unless your goal is to be a girly-man. Luckily, glutamine is one bad mo-fo that bitch-slaps cortisol and stops it dead in its tracks. As a matter-of-fact, glutamine has proven to be so powerful in stopping muscle breakdown that it is actually used at some hospitals to treat patients with acute muscle atrophy.
Glutamine does not just stop muscle from being broken down, it also works as an anabolic agent to build new muscle. There have been various studies done, including one in the American Journal of Clinical Nutrition, that show supplementing with glutamine will increase growth hormone levels by up to 400%! Considering that growth hormone works synergistically with other hormones such as testosterone to make you grow like a weed, raising your GH levels four-fold would be a great way to get that extra muscle you always wanted.
Anabolic reason number two to keep glutamine in your supplement cabinet at all times is that it plays an important role in protein synthesis. In addition to helping and increasing protein synthesis, glutamine transports nitrogen through the body and is critical to your body keeping nitrogen balance. The ability to increase the amount of proteins that your body can manufacture will have a huge affect on your ability to add muscle. As many of you may already know, keeping a positive nitrogen balance in your body will also determine your ability to develop new muscle.
Another great thing that a higher level of GH will do for you is to increase the rate at which you burn fat. Growth hormone stimulates lypolysis, which is the breakdown of fat that is stored in the fat cells. So not only will your muscles be much larger, there will be less fat covering them to make them look that much more impressive, and your waist will also be smaller to give you a taper that makes you look like you have wings.
Increasing growth hormone and protein synthesis are great ways to add muscle, but being able to increase the intensity of your workouts will help you just as much, and glutamine can do this in a couple of ways. Some studies done at Louisiana State University showed that a dose of only 2 grams of glutamine increased bicarbonate levels over a 90-minute period. The importance of this is that this will enable your body to buffer the effects of lactic acid. If lactic acid cannot attack the muscle, then the soreness and fatigue that accompanies it will not force you to stop your set short. The result is more reps and sets at higher intensity levels, and thus… more muscle.
Another study presented at the American College of Sports Medicine had subjects undergo comprehensive workout sessions, and then they took either glutamine or a placebo. This study lasted for six days. The subjects who ingested glutamine supplements did not experience any decreases in strength over days one to six. Their counterparts, the placebo group, showed a decrease in strength, which meant that their muscles were not recuperating. In addition, during day six, the glutamine group was able to maintain training intensity before fatigue set in for a greater duration than on day one. The placebo group was not able to improve workout duration. This led the researchers to believe that taking glutamine supplements in between training sessions would help increase recovery. In short, supplementing with glutamine allows you to train harder and more often without experiencing overtraining.
The average bodybuilder will get somewhere between 3-6 grams of glutamine per day from the sources of protein they consume. However, as a bodybuilder that is training intensely every day, your body will need much more. In order to keep glutamine levels where they need to be, bodybuilders should consume about 0.1 grams of glutamine per every kilogram of body weight following your workout. They should take an additional 5-10 grams throughout the pre-workout period of the day.
You train hard in order to accomplish your goals in the gym; do not allow a lack of nutrition to defeat all your effort. Supplementing with glutamine will increase protein metabolism to enable you to add massive amounts of muscle, and it will also increase growth hormone levels, keep your digestive system functioning properly, and inhibit the negative effects of cortisol and lactic acid. Most supplements are used for a specific purpose, but glutamine will give you a wide spectrum of benefits that will enhance your ability to add muscle and burn fat. In the supplement world… glutamine is one of the best when it comes to getting a big bang for your buck.