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Marines

Study weighs pros, cons of nutritional supplement use

11 May 2000 | Lance Cpl. Marine Corps Logistics Base Albany

It is a common perception around the gym and with weightlifters that nutritional supplements such as Glutamine, Creatine, or dehydroiepiandrosterone and androsterone, commonly referred to as estrogen, are necessary to obtain the desired muscle mass.
Is this true? Do you really need synthetic or herbal extracts to increase muscle mass or endurance?
Are there adverse effects from taking supplements?
Although there are varying opinions from medical practitioners and researchers, there is a general consensus that anything that is put into the body has the potential to cause adverse side effects, especially if taken incorrectly.
Glutamine is an amino acid widely used to maintain good brain function such as improved mental alertness, clarity of thinking and mood.
Glutamine is a derivative of glutamic acid that is synthesized from the amino acids ornithine and proline.
Because glutamic acids cannot cross the blood brain barrier, which is where most of the bodies metabolism takes place, glutamine, which can cross that barrier, works better in supplement form.
Glutamine can also be used by cells like glucose for metabolic energy, thus a popular supplement.
Glutamine is also the most plentiful free amino acid in the bodies muscle tissue and plays a very important role in protein metabolism, cell volumizing, and anti-catabolism, which means that it may help prevent muscle breakdown.
Under periods of stress as intense workouts, glutamine becomes critical because the body may not be able to make enough of it.
Studies show that glutamine supplementation is an effective way to replace these declining levels and thus help maintain peak athletic performance.
However, according to William D. McCardele and Victor Katch, leading medical researchers for Sports and Exercise Nutrition magazine, The body absorbs the simple amino-acid molecules more rapidly to optimize the expected muscle growth brought on by training to acutely improve strength, power or vigor for a heavy workout.
This however, does not occur.
The healthy intestine also absorbs amino acids rapidly when they exist in more complex di- and tripeptid molecules, and in simple amino acid form.
The intestinal tract handles protein quite efficiently in its more complex form, whereas a concentrated amino-acid solution draws water into the intestine, often precipitating irritation, cramping and diarrhea.
Simply stated, adequate research design and methodology has not shown that amino acid supplementation in any form significantly increases muscle mass or improves muscular strength, power or endurance.
DHEA and ANDRO are two compounds called steroid precursors, which are converted to estrogen and testosterone in the body.
DHEA has been marked as steroid replacements to increase the development of muscle mass in body builders and resistance weight trainers.
It has also been promoted as a product which will prevent heart disease, cancer and osteoporosis, promote youth, boost the immune system, and improve many physiological states.
There is no scientific evidence that supports any of these claims.
DHEA can have severe side affects.
Chronic use increases the risk of male characteristics developing in a female, such as excessive facial hair and thickening of the vocal cords, and female characteristics developing in a male including testicular astrophy.
DHEA also elevates blood sugar levels, cholesterol and high-density lipoprotein levels, and produces liver problems.
Of even greater concern, DHEA has also shown to increase the development of certain types of cancers, and worsen existing cancers by accelerating the rate of growth.
ANDRO is also a steroid precursor and thus will show the same effects as DHEA and the same adverse consequences on health.
Both DHEA and ANDRO have been banned by several sports governing bodies including the U.S. Olympic Committee, the International Olympic Committee, and the National Football League.
According to Lt. Cmdr. Patricia Rose, Nutritional Management Department, Naval Hospital Jacksonville, Fla., service members whose career in the military may hinge on whether or not he or she can achieve necessary standards of weight loss or physical fitness should not be encouraged to use a product which might impact them financially, increase their risk of sudden death, and impede assistance needed from component health care providers to achieve health standards.
I do not feel that our facilities should convey the message that to participate in a sport or gain muscle mass, the individual must use supplements, Rose added.
Another supplement, and a more popular and a more wide spread one, is creatine.
Creatine, which is usually sold in supplemental form as Creatine monohydrate, is a fairly new supplement that serves as energy reserve in muscle cells. Muscular contraction is powered by the breakdown of adenosine triphosphate to adenosine diphosphate.
When all ATP is broken down, creatine phosphate in the muscle donates a phosphate group to ADP, and further energy reactions can occur. Creatine monohydrate is a precursor to creatine phosphate.
By supplementing with CM, CP levels in muscle apparently are maximized, and more muscular work can occur, since there are greater energy reserves to use.
Creatine also helps with resistance training by bloating the muscle with creatine rich fluid.
This allows for greater leverage and requires the muscle to move less and lift more weight.
While this may seem kind of trivial, some researchers today think that one of the stimulating factors of steroid use is water retention.
Anabolic steroids may actually work in part because of cellular fluid retention in the muscles.
The swelling action and the related stretching of the cells may in and of itself cause a reaction that stimulates the muscle cells to grow.
As for good aspects for the use of creatine, many people report increasing their lean muscle mass between six and 10 pounds while using CM, though gains seem to stop after that point.
CM is also nontoxic, even in large amounts.
Usually, the use of creatine is split into a loading and maintenance phase.
During the loading phase, large quantities of creatine monohydrate are taken.
Because the creatine only slowly disappears from the body, a maintenance phase in which less creatine is taken will still improve the body with adequate levels of creatine.
While using creatine or any of its byproducts, it is strongly recommended to consume large amounts of water and it is also recommended not to use caffeine while on creatine.
Some side effects of taking CM may include headaches, clenched teeth and the sound of blood rushing through the ears while using the product.
Creatines effects on blood pressure are an open question. Since it has the effect of fluid retention on muscle, it might increase blood pressure in the same way high sodium levels do, but this has not been established or refuted.
As for the question on whether supplements are good or bad, in general, it depends on the individual, the amount and frequency of the supplement taken, and if there is any combination that may cause adverse effects or  that cancel each other out.
The best advice that can be given, according to Rose, is to contact your local primary care physician before beginning supplement training to see if its the right supplement for the individual and the training that is planned.
Marine Corps Logistics Base Albany