Although it is less familiar to the average athlete than creatine monohydrate, many experts feel that glutamine actually has more long-term potential for promoting growth, strength and health than creatine. Creatine works, but glutamine also works, and it does a lot more things than creatine. Creatine is the best at what it does, but glutamine is much better all-around.

Glutamine is an amino acid, one of the building blocks of protein. But it’s much more than just a building block for proteins. It has so many critical roles in so many physiological processes, especially those related to maintaining and growing muscle mass, that even scientists consider it a legitimate nutritional supplement. And athletes, from bodybuilders to marathon runners, are increasingly accepting it as an indispensible part of their supplement array.

Glutamine is the most abundant amino acid in the body. It’s especially concentrated in muscle where it makes up more than 60% of the “free” amino acids, which are readily available for various uses by the muscle or by other parts of the body. Although glutamine was once considered a non-essential amino acid, meaning that the body did not need to take it in but could synthesize it from others, it’s recently been elevated to the status of a conditionally essential amino acid, meaning that while the body can make glutamine, there are circumstances in which the need outstrips the rate at which it can be made.

Glutamine is considered such a good supplement for many reasons. Number one, serves as a direct regulator of protein synthesis and breakdown in muscle. Muscle tissue is the major site of synthesis and storage of glutamine. As doctors and scientists have been discovering over the past two decades, any type of stress; trauma, surgery, burns, infections, fasting, malnutrition, and hard or prolonged exercise causes glutamine to be released from muscles. The losses are proportional to the stress, and during the more extreme states of stress or catabolism, glutamine stores can be very rapidly depleted.

This depletion occurs because glutamine is needed more critically by other tissues of the body which cannot synthesize it, like the immune system and the intestines. After all, the immune system does play a critical role in the repair of tissue damaged by intense exercise.

Once depleted, glutamine is virtually the last nutrient to be restored to prestress levels. What’s so important about this is that many experts feel that the amount of glutamine in muscle is the single most important factor influencing the rates of protein building and breakdown.

When glutamine leaves muscle, there is no glutamine available for incorporation to any muscle proteins that could have or would have been built, and branched-chain amino acids (BCAAs) are less available for protein synthesis because they are used by the muscle to make up more glutamine.

When glutamine leaves muscle, the muscle begins to dehydrate. And it’s now well known by bodybuilders, as well as scientists, that dehydration leads to protein degradation. Conversely, as you might expect, increasing the amount of water inside muscle fibers; which glutamine does, although not quite as dramaticallyas creatine, leads to an increase in protein synthesis.

Studies with animals and many different groups of patients have demonstrated that adding glutamine to their nutrient intake can reverse protein catabolism and loss of muscle mass. Even though these studies have not been conducted on healthy human athletes, the basic physiological responses to the situation are very similar to those of hard training; and it’s strongly suggestive that in these studies glutamine prevented the loss of what are called myosin, heavy chain proteins, because these are the ones that determine a muscles contractile properties and capabilities.

Overtraining in athletes, all too common in serious bodybuilders, can lead to glutamine depletion and a weakened immune system, in addition to impaired energy and performance. Experts have, in fact, suggested that plasma glutamine concentrations can be used as a measure of both the relative state of overtraining and the recovery from this condition. Again, animal studies indicate that supplemental glutamine can mitigate or neutralize the loss of muscle glutamine following exercise.

In another study, glutamine infusion, prior to exercise, resulted in an increased muscle glycogen concentration two hours after exercise causing the researchers to speculate that glutamine might serve as a direct precursor for muscle glycogen replenishment after exercise.20 Glutamine has also been shown to affect the metabolism of free fatty acids and fat deposition, all in ways that reinforce its potential benefits for over weight individuals, as well as bodybuilders and other athletes.

The glutamine-GH connection is another reason to include this nutrient in your supplement array. A recent study found that an oral dose of only two grams of glutamine significantly elevated growth hormone release, which is conducive to gains in muscle mass. Although unreplicated as yet, this study suggested that small doses can make it pass the gut and liver reaching the brain, muscles, and other organs; and that small doses may be able to exert profound physiological effects. Another interesting study found that glutamine, along with glutamate, has a role in increasing gonadotrophin-releasing hormone (GnRH) release and thus indirectly may increase testosterone secretion.

To maximize recovery and growth, you have to keep glutamine stores in muscle topped off every day. This is not a supplement that you need to or should cycle. As long as glutamine content remains high in the cell, cell hydration and anabolic processes remain elevated. When glutamine leaves muscle, the cells lose water and catabolic processes begin.

You can get glutamine from food as it makes up roughly 4-8% of most food protein with the highest concentrations occurring in milk, meat, and some nuts. You may get as much as 10 grams a day from your diet, but that’s not optimal for serious training. And since the cells of the intestines are such voracious consumers of glutamine, not much makes it through to your muscles except in very high protein diets. To keep your muscles really flush, you probably need around 20-25 grams a day in your diet and maybe more during the more extreme periods of training and/or dieting. That means supplementing. And not just with glutamine-enriched protein supplements. They may help, but they won’t usually give you that much unless you use very large amounts every day.

The simple, easy way is to use a supplement consisting of pure glutamine powder. Simply take a teaspoon three or four or even five times a day: when you get up, before bed, before and after your workout, and maybe one other time. You can put it on your tongue and then take a drink. You can mix it in a little water. It has very little taste, and certainly not an unpleasant one.