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Myostatin Inhibitor the next big thing in Bodybuilding?


You may have seen the pictures of the Bull or Dog with amazing muscular development. You may have heard that Myostatin inhibitors can double the size of your muscles AND cut fat at the same time. You may also have heard that the side effects are slim to none. So you may have been asking yourself – “Well where can I get ahold of Myostatin inhibitors” or “Is this the next big thing in Bodybuilding?” Or “Could there be others that would benefit greatly from Myostatin inhibitors such as people with muscular dystrophy?”

Before venturing into answering these questions let me begin with a definition of Myostatin.

Myostatin defined

Myostatin is a protein, which was discovered by researchers at Johns Hopkins University in 1997. The word Myostatin means “muscle stopper,” which accurately describes what Myostatin does in the body. Scientists aren't sure how Myostatin works, but the leading theory is that it inhibits the involvement of satellite cells, or immature muscle cells, in muscle growth. That's the opposite of what several anabolic hormones, particularly insulin like growth factor 1 (IGF-1), do.

(For the medical definition please see the menu item on the left.)


Animals without Myostatin

Animals born without the gene that codes for myostatin have two primary characteristics: They have much larger muscles than usual, and they have less bodyfat than usual. Other than that, they appear normal, with no obvious physical problems.                                                       















Why this is interesting to bodybuilders

Myostatin is a topic of enormous interest to bodybuilders, since, theoretically, if you can somehow block its effects, your muscles will grow very rapidly. It is believed that weight training is an effective myostatin blocker, which accounts for some of the growth that comes from regular training. In animals, blocking myostatin activity or manipulating their genes so that they don't produce myostatin yields not only increased muscular growth but also a dramatic reduction in bodyfat. The theory is that the lack of myostatin produces a repartitioning effect, promoting muscle growth at the expense of bodyfat. In short, bodyfat is used as a source of energy to support muscle growth. In other words, a bodybuilder using Myostatin inhibitors potentially gains the best of two worlds: Larger muscles and lower levels of bodyfat.

Possible sideeffects of myostatin inhibitors

A study in mice performed at the University of Michigan, suggests that while Myostatin inhibitors may indeed bulk up muscles, they may also bring a troubling side effect – small, brittle tendons that could make muscle injuries more likely.

“Those interested in Myostatin inhibitors need to be aware of the fact that by doing these things to muscles, they may be having negative effects on tendons,” says John A. Faulkner, Ph.D., the study's senior author and professor in the Department of Molecular and Integrative Physiology at the U-M Medical School. He is also a research professor at the U-M Institute of Gerontology and professor of biomedical engineering at the U-M College of Engineering. The study results appear in the Jan. 8 print issue of the Proceedings of the National Academy of Sciences.

“When you lift weights at the gym, muscle tissue gets damaged. That sets off the release of Myostatin, starting a process that clears away damaged proteins and sets the stage for muscle rebuilding”, says the study's first author, Christopher L. Mendias, Ph.D. The study suggests we need normal Myostatin action for other reasons, too.

“It also appears to make tendons bigger and more flexible,” says Mendias, a U-M post-doctoral research fellow in the Regenerative Sciences Training Program in the Department of Surgery at the U-M Medical School.

It is known that blocking Myostatin's activity increases muscle mass and strength, but also makes muscle fibers more vulnerable to injury. The U-M team broke new ground by asking if Myostatin also affected the make-up and performance of tendons, the fibrous, tough tissues that connect muscle to bone.

Tendons are stiffer than muscles to begin with, and get stiffer with age. If tendons are brittle and short, as they were in Myostatin-lacking mice in the study, they can't adequately do their important job of buffering against muscle injuries. These results are intriguing and cautionary for the variety of people interested in the potential of Myostatin inhibitors to increase muscle mass.

 Will Myostatin Inhibitors become a mainstream over-the-counter product?

It is hard to say. If there are no known sideeffects of the products, or these are limited, and people want a faster way to get in shape, then there is a market. It will likely be developed for the medicinal industry to aid those with Muscular Dystrophy, elderly loosing musclemass, and for other areas where a need for rapid increase in musclemass is beneficial to reaching a better life or recovery. A question to ask is whether the Supplements industry would market Myostatin Inhibitors. Doing so would cannibalize their own products such as Creatine and Protein supplements as well as many others, as the intake of Myostatin inhibitors, would make the need for intake of these other products pointless. The supplement industry is a multimillion dollar industry and thus it is unlikely, they would engage in this, as the loses from lack of sales would be too vast. Of course they could just set the price high enough – but they would still hurt the sales, of the other supplements.

There are, however already signs of a nascent black market for what might become another illegal performance-enhancing drug in organized sports.




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