Monday, August 13, 2001

GLUTAMINE - part 1
Reach Your Peak With Glutamine

You know about the importance of eating enough protein every day. It provides vital amino acids for your body, helping you build a defined, muscular physique while enjoying good health. But did you know that the usually recommended amount of protein is still not enough to reach your peak in muscle mass or optimize your immune system? It's true: Even protein intakes exceeding the RDA can provide less of the amino acid glutamine than you need. Studies have shown that you must supplement with this important nutrient if you want to get the most from your diet and exercise program.

Glutamine is the most abundant amino acid in the human body. The majority of which is stored within the skeletal muscles, although significant amounts are also found in the blood, lungs, liver, and brain. Glutamine is involved in more metabolic processes than any other amino acid in the body. And while it shares many characteristics with the other amino acids, it does have one major difference: Because it has a nitrogen atom to spare, glutamine is able to transport nitrogen around the body. This allows it to perform some of its unique functions.

Gets Rid of Lactic Acid

When you engage in intensive exercise, it often leads to a "burning" sensation that eventually becomes so strong you have to stop for a few minutes. This "burn" is produced by lactic acid, which is a byproduct of anaerobic glucose and glycogen metabolism during muscle contraction. Glutamine plays a vital role in regulating the body's acid-based balance. It gives rise to the production of bicarbonate ions by the kidneys, which neutralizes some of the lactic acid. The kidneys also break down glutamine to produce ammonia in a multi-step process. This neutralizes even more of the lactic acid. During periods of high-acidic concentrations, these two mechanisms can increase glutamine consumption in the kidneys six to ten times over the normal rate. The greater the availability of glutamine, the greater the potential for rapid restoration of the body's acid-based balance. This can allow you to resume exercise sooner and may even permit higher levels of force production during your workout.

Boosts Growth Hormone

Growth hormone is one of the most important hormones in the body. Secreted by the pituitary gland, it plays a major role in muscle growth and retention due to its ability to promote cell division and proliferation. It does this by increasing the amount of amino acids transported across the cell membrane. Growth hormone also promotes the growth of bones and connective tissue. It also increases the level of free fatty acids in the blood, resulting in a greater use of fat as an energy source and the sparing of available protein and carbohydrates. By raising the body's energy expenditure at rest, it helps to reduce your body-fat level, too.

A study by researcher Thomas Welbourne found that oral glutamine supplementation has a dramatic impact on growth hormone secretion. A dose of only 2 gm following a light breakfast increased growth hormone levels by 430% over baseline levels after 90 minutes! There was an increase in plasma bicarbonate concentration as well, which confirms that oral glutamine supplementation is an effective way to reduce lactic acid levels. Since growth hormone concentrations decline with age, such dramatic increases are especially good news for people entering middle age and beyond.

Fights Catabolic Reactions

Glutamine plays an important role in fighting catabolic reactions in the body, thereby promoting the greatest anabolic response to exercise. During intensive training sessions, microcellular damage to the muscle tissue usually occurs, along with increased secretion of the catabolic hormone, cortisol. These two factors result in an initial breakdown of muscle. Eventually, the body overcomes these negative forces and begins to build new muscle tissue (protein synthesis). The time it takes for this to occur, however, depends on your level of nutrition and supplementation.

While branched-chain amino acids (BCAAs) have sometimes been recommended to fight catabolism, several research studies have shown that glutamine is superior to the BCAAs in promoting protein synthesis. Glutamine peptides have also been shown to prevent the muscle atrophy induced by high cortisol levels. Glutamine also increases water levels inside the muscle cell, although the increase is not as pronounced as with creatine. This higher intracellular water supply enhances protein synthesis, providing more raw materials for building new muscle tissue. Glutamine even promotes the storage of muscle glycogen, a vital energy source during high-intensity training. Despite its importance in muscular development, glutamine is virtually the last nutrient to be restored to pre-exercise levels. This makes supplementation essential if you want to maximize the gains from your training program. Glutamine supplementation will also allow the other amino acids in your food to be used for their intended anabolic purposes, enhancing the biological value of your entire protein intake.

Improves the Immune System

There is no doubt that strenuous exercise can tax the immune system. Numerous studies have shown a higher incidence of infections and cold symptoms following a bout of intense exercise. Glutamine depletion appears to be partly responsible. A study by L.M. Castell and colleagues found a significant drop in the plasma level of glutamine in endurance athletes after a marathon. However, when these researchers gave 5 gm of glutamine to more than 100 athletes, they discovered that only 19% of them reported infections during the next seven days, compared to 51% of the athletes in the placebo group. Glutamine's anti-catabolic benefits are also used to promote recovery in hospital patients. A wide range of studies reported improvements in immune parameters when glutamine is added to the meals of bone-marrow transplant and chemotherapy patients as well as burn and trauma victims. Clearly, glutamine is powerfully beneficial!

Glutamine supplementation helps to keep you healthy and strong in many ways. In fact, when you consider how inexpensive this amino acid is, it could be one of the most cost-effective supplements on the market today.

GLUTAMINE - part 2
Glutamine and the Over-Training Syndrome

Most weight trainers and other athletes are familiar with the Over-training Syndrome. Excessive training with insufficient rest intervals can result in an over-trained state, which in turn, leaves the athlete at risk of muscle or connective tissue injury, infection, chronic fatigue, and under performance.

Strangely enough, one of the "nonessential" amino acids - glutamine - appears to play a key role in preventing Over-training Syndrome. Although classified as nonessential because it can be synthesized from other amino acids, glutamine is in face, the most abundant amino acid in human muscle and blood. It is critically important for growing and regenerating cells, including those found in exercised muscle tissues, and white blood cells. During catabolic states such as surgery, injury, infection and the recovery period following high intensity exercise, glutamine supplies are taxed, and the body cannot manufacture it from other amino acids nearly fast enough to meet the demand. To sustain tissue growth and healing, and to turn catabolism into anabolism, glutamine must be supplied from somewhere else, namely, dietary protein, or supplementation.

Several recent scientific articles on the Over-training Syndrome discuss the relationship of glutamine nutrition to the symptoms of over-training. Athletes with these symptoms have lower levels of plasma glutamine at rest than active healthy controls. These reduced levels of glutamine impact white blood cells, reducing the ability of the immune system to ward off infection.

In catabolic stress states, including the recovery period after exercise, tissue requirements for glutamine are increased, while plasma glutamine is depleted. This is, of course, the period during which it is MOST CRITICAL to maintain proper nutrition in order to GAIN strength from the precious workout, rather than lose it! In fact, it takes several hours for normal (pre-exercise) levels of glutamine to be restored. The problem is compounded if the athlete does not allow for adequate recovery periods between workouts, creating a serious shortage of glutamine. Eventually, the Over-training Syndrome sets in, accompanied by low plasma glutamine levels that can persist for months or years.

Clearly, this data makes a strong argument for high-protein supplementation immediately before and after workouts, and for glutamine supplementation for several hours or days after workouts. Without adequate glutamine, not only are the benefits of the previous workout lost, but the entire body is put at risk of eventual Over-training Syndrome - with its staleness, tiredness, injuries, infections, and all the rest. If you currently suffer from over-training, crank up the glutamine and total protein intake, and give you body a chance to re-accumulate its reserves.