Myostatin is a human growth factor that prevents excessive muscle growth, and abnormally high levels can cause the loss of muscle mass. Myostatin is also a hot topic among athletes and bodybuilders, who claim that inhibiting it can boost muscle growth. Read on to learn about the benefits of inhibition and some foods that can help.
What is Myostatin?
In both humans and animals, myostatin is a hormone that acts as a sort of “brake” that tells muscles to stop growing, which helps to prevent them from getting too large.
This is important because past a certain size, adding more mass to muscles doesn’t actually make them stronger – and muscles that are too large are also more vulnerable to damage. Over-developed muscles can also get in the way of other important organs, reducing their size and impairing their functions [R, R].
Myostatin is active during multiple stages of the life cycle. Before birth (during embryonic development), myostatin determines the total number of muscle fibers an individual will have.
In humans, myostatin levels also often increase with age, which may contribute to the loss of muscle mass during aging [R].
Myostatin levels are significantly higher in patients with diseases like amyotrophic lateral sclerosis (ALS), Duchenne muscular dystrophy, and multiple sclerosis, which all involve the significant loss of muscle mass. Therefore, inhibiting myostatin may help prevent the loss of muscle in these diseases [R, R].
Myostatin is produced by the muscle tissue of the heart, and damage to the heart causes it to be released into the bloodstream. Once in the bloodstream, myostatin reaches the muscles and causes them to weaken over time. As a result, patients with heart disease often also experience symptoms of muscle atrophy (muscle loss) [R].
It has recently been shown that knocking out the genes responsible for producing myostatin in the heart prevented heart disease-related muscle damage in mice, suggesting that myostatin inhibition might be a useful way to prevent muscle damage in humans with heart disease [R].
Benefits of Inhibiting Myostatin
1) Myostatin Inhibition May Prevent Muscle Degeneration
Inhibiting myostatin can affect muscles in several different ways.
First, some evidence suggests that inhibiting myostatin can prevent muscle from weakening during long periods of inactivity. For example, myostatin inhibition reduced the loss of muscle in young mice that were prevented from using their hind legs for 21 days [R].
Secondly, myostatin inhibition can also prevent muscle loss that happens as a result of other diseases. For example, deleting the genes involved in producing myostatin in the hearts of mice prevented the severe muscle and weight loss caused by heart failure [R].
In mice with chronic kidney disease, inhibiting myostatin slowed the muscle loss caused by kidney disease and enhanced the growth of forearm muscles [R].
Over 20% of cancer deaths in human patients is caused by cachexia, a symptom of cancer that causes the loss of muscle and fat despite adequate nutrition. However, multiple studies in mouse models have shown that myostatin inhibition can prevent this cancer-related muscle loss in both lung and skin cancer (melanoma). This suggests that inhibiting myostatin may be an effective way to prevent a significant number of cancer deaths in human patients [R, R, R].
Duchenne muscular dystrophy (DMD) is an incurable disease that causes the loss of muscle tissue. However, myostatin inhibition has been shown to increase muscle mass in both dogs and mice with DMD, suggesting the future potential to treat human patients with myostatin inhibitors [R, R].
Finally, myostatin inhibition prevented muscle weakness and muscle loss in mice with Huntington’s Disease, an inherited genetic disorder that causes muscles to degenerate over time [R].
2) Myostatin Inhibition May Help Build Muscle
A case study of a human child with unusually high levels of muscle development reported that the child also had very low levels of myostatin, providing evidence for a direct link between myostatin inhibition and enhanced muscle growth in humans [R].
A pilot study using compounds that inhibit or decrease myostatin levels found that just 7 days of treatment increased grip strength in 6 middle-aged human subjects, further suggesting a direct link between myostatin and muscle development in healthy humans [R].
Similar connections have been observed in both mice and cattle, where genetic mutations that impair the creation of myostatin in the body result in “double-muscled” animals that have up to 20% more muscle fibers than normal, as well as dramatically reduced levels of body fat [R, R, R, R].
3) Myostatin Inhibition May Prevent Obesity
In addition to affecting muscle growth, inhibiting myostatin may also help prevent the accumulation of fat in the body.
In mice, using follistatin to inhibit myostatin led to reduced fat gain, and also decreased the size of fat-storing cells (adipocytes) [R].
Foods and Supplements that Inhibit Myostatin
Myostatin can be inhibited in humans by taking supplements, as well as by eating foods that are rich in nutrients that can indirectly affect myostatin activity in the body.
Creatine is one well-researched and safe myostatin inhibitor. Added to resistance training, creatine can increase the growth potential of muscles by lowering myostatin. In one study on healthy 27 men, creatine prevented increases in myostatin, which adds to its amplifying effects on muscle-building in power athletes [R].
For example, one notable method of inhibiting myostatin is through the consumption of epicatechin, a member of the flavonoid family of chemicals that control pigmentation in plants [R].
In old mice, daily injections of epicatechin led to increased overall muscle strength. The same treatment in 6 human subjects increased their hand grip strength after just 7 days [R].
- green tea
- chocolate (especially dark chocolate and raw cocoa powder)
- broad beans
Eating these foods is, therefore, an easy way to reap the benefits of myostatin inhibition [R].
Certain workout supplements also act as myostatin inhibitors. Many of these supplements contain follistatin, a compound proven to block the actions of myostatin. Although there are not many human studies about the effects of follistatin on muscle growth, animal models and user reviews provide some support for their effectiveness.
For example, follistatin increased muscle mass in mice through its ability to decrease myostatin in muscles [R].
One workout supplement that contains follistatin is MYO-X, which uses follistatin from egg yolks. MYO-X was found to increase muscle mass in 37 healthy college-age male athletes when taken at 10 to 30 grams per day [R].
Side Effects of Inhibiting Myostatin
Myostatin inhibitors have become popular athletic supplements to use for fast muscle growth [R].
However, there are several potential downsides to be aware of when using myostatin inhibitors for athletic enhancement.
One potential concern is that increased muscle growth will lead to an increased risk of injury due to increased stress on the muscle fibers. This is especially true for individuals using myostatin inhibitors as workout supplements instead of as part of a medical treatment for muscular dystrophy or other disorders [R].
Other possible side effects of myostatin inhibitors include increased the chance of tendon rupture, heart failure due to inflamed cardiac muscle, and rhabdomyolysis, a breakdown of muscle fibers that often leads to kidney failure [R, R].
Myostatin Inhibitors in Sports
Despite the potential benefits of myostatin inhibition, the athletic community often views its use as cheating or immoral. Not much scientific research has gone into its other adverse effects when used for athletic enhancement [R].
One common way to inhibit myostatin is through “gene doping,” where human DNA is directly altered to grow muscle more easily. This is often done in secret due to its ban in many athletic communities. However, this secrecy also leads to a lack of safety in the procedure, which can have unpredictable consequences [R].
While there are many different ways to use supplements and foods to influence myostatin levels, most of the user experiences on the net come from athletes who have used supplements like MYO-X to enhance their muscle growth:
“This is the best product for bodybuilders or those who love bodybuilding.”
“I have been taking MYO-X for more than a year. Together with regular exercise, it helps to keep my body in shape.”
“MyoX definitely takes my workouts to the next level! Remembering to take it the night before morning training is the only reason it’s not a 10!! At 47, I’m no stranger to the supplement game and saying that using MyoX over the past few years, it’s quite obvious that it’s a game changer!”
“Myo-x has 100% helped my soreness levels and I no longer have to ice my shoulder after every workout. My training volume has gone up greatly since taking it and consequently, my strength.”
“I tried it and it helped my gains a lot. Saw results a lot quicker than before and with the right diet you will see gains easy!”
“Unfortunately, this product does not perform what it claims. I took this product for two months and noticed no increase in strength or muscle mass when taken every day with proper diet and workout routine.”
“I can’t stress enough that the effects of Myo-X really demand added protein/nutrition above and beyond what you may already be used to…insufficient building blocks equals little benefit, and Myo-X is helping direct more bodily resources to muscle.”