Understanding Myostatin: The Bodybuilder's Dilemma

What is Myostatin?

Myostatin is a hormone that initially appears to be every bodybuilder's worst nightmare. Its name means “muscle stasis,” and its primary function is to inhibit muscle growth. However, the story of myostatin is more complex than it seems.

How Myostatin Works

Myostatin, also known as Growth Differentiation Factor 8 (GDF8), is part of the Tumor Growth Factor Beta family. This hormone is encoded by the MSTN gene. Here’s how it operates:

1. Binding to Receptors: Myostatin binds to the activin type II receptor on myoblasts—these are immature muscle cells.

2. Inhibiting Growth: This binding prevents myoblasts from developing into full muscle fibers.

3. Stopping Protein Synthesis: Myostatin also halts muscle protein synthesis. Its primary role seems to be controlling how big muscles can grow. It acts against the growth-promoting effects of IGF-1.

   
   

The most proven method to reduce myostatin release is through the use of creatine.

Evidence from Animal Studies

In research involving mice, disabling both MSTN genes resulted in them having twice as much muscle mass as normal mice.

Myostatin in Cattle Breeds

A cow exhibiting pronounced muscle development due to myostatin inhibitors, showcasing the impact of genetic alteration on livestock.

Certain cattle breeds, like the Belgian Blue and Piedmontese, have inactive myostatin hormones. These breeds can produce 40% more muscle than other cattle. Even a modest 20% reduction in myostatin leads to a significant increase in muscle mass. However, a complete absence of myostatin can make bulls so muscular that they cannot reproduce. They also require excessive amounts of food, making them economically impractical for farmers.

Myostatin Research in Dogs

A muscular dog exhibiting myostatin deficiency, showcasing an unusually robust physique due to this genetic condition.

The National Institute of Health (NIH) studied racing Whippets and found that many top competitors were heterozygous for the MSTN gene. This means they had one functional MSTN gene. Conversely, dogs with no functional copies of MSTN displayed significant muscle growth. However, these homozygous dogs performed poorly, exhibiting unwanted traits such as short limbs and overbites. Nonetheless, they remained friendly, lovable pets.

Myostatin Inhibition in Humans

Two children showcase remarkable muscle development due to myostatin deficiency, highlighting the condition's impact on muscle growth.

In humans, a non-functional MSTN gene leads to increased muscle synthesis. If both genes are non-functional, muscle protein synthesis is even greater. There are also cases of children who lack myostatin receptors, leading to overly muscular physiques.

To combat this, researchers developed a monoclonal antibody targeting myostatin. This antibody acts like a free-floating receptor, preventing myostatin from binding to muscle receptors. These antibodies have shown promising results, yielding up to a 60% increase in muscle cells—similar to effects observed in certain cattle breeds.

The Relationship Between Myostatin and Heart Health

Interestingly, the heart is also a muscle. However, unlike skeletal muscles, we don't want the heart to grow larger. Although the heart produces less myostatin than other muscles, it still produces some.

Inhibiting myostatin could have unintended consequences, causing the heart to grow excessively. When the heart can't pump enough blood, it enters a state known as heart failure. In this situation, the heart attempts to enlarge itself to meet increased bodily demands. However, myostatin acts to slow or halt this growth.

The Impact on Gains

Myostatin leaks into the bloodstream and can prevent muscle growth elsewhere. If an athlete neglects heart health, the heart's condition could negatively impact muscle gains.

A Focus on Bodybuilding Aesthetics

Bodybuilding is about achieving the best physique, not necessarily the largest. Inhibition of myostatin may lead to unintended growth of abdominal muscles, even without specific training. The art of bodybuilding emphasizes a small waist for a balanced and aesthetically pleasing physique.

If the goal is to enhance certain muscle groups without increasing the size of others, strategies should involve targeted training. Rather than simply building bulk, athletes should focus on specific muscle development.

You can achieve this with structured lifting techniques, proper form, and nutrition. If you need assistance, consider my 2-Month Coaching Packages or book a 30-Minute Phone Consultation to discuss personalized strategies.

Conclusion

Myostatin plays a crucial role in muscle development and management. While its inhibition may seem advantageous for muscle growth, careful consideration must be given to heart health and overall body aesthetics. A balanced approach will ensure sustained gains without compromising overall fitness.

You have questions, I have answers. Book a 30-Minute Phone Consultation with me today! 30-minutes not enough? Don't worry. I also offer a variety of 12-Month Coaching Packages.

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Disclaimer

Nothing in this article or on this site should be considered medical advice or an endorsement to violate any law of the country in which you reside. The information given is for fun and entertainment purposes only. All claims are 100% dependent upon proper diet and exercise. Please consult a medical practitioner prior to any diet and exercise program.