Myostatin

Myostatin

myostatin deficient dog

Wendy the myostatin deficient dog

is a cytokine which functions as an antagonist for Insulin-like Growth Factor-1. It is therefore a negative regulator of muscle growth. In other words, it causes the breakdown of muscle tissue. It is an essential substance in maintaining balance in protein synthesis and protein breakdown. This is most obvious in animals that have mutations in their DNA, rendering the myostatin gene less active or even completely shutting it down. These animals have an highly increased muscle mass and look like bodybuilders among their species. This reduces muscle function as well, since myostatin also serves to improve muscle quality. However it also plays a major role in diseases such as muscle dystrophy, where myostatin activity is increased and muscle mass decreases progressively.

Aside from helping increase muscle fiber quality, myostatin is also important during periods in which food is scarce. By decreasing the amount of muscle mass, the amount of energy you need goes down as well, which increases your chances of survival. Since finding enough energy is hardly a problem in Western society these days, myostatin is less usefull in this respect.

In healthy humans, myostatin regulation can be influenced by exercise and diet. Especially resistance exercise reduces the myostatin genes’ activity, allowing muscle hypertrophy. In addition meals rich in protein and supplements such as whey amino acids also down regulate myostatin activity, improving muscle building conditions, and ultimately leading to increases in muscle mass and strength.

In summary, myostatin causes the breakdown of muscle tissue, but when you supply your body with an adequate stimulus for muscle growth such as strength training and adequate nutrition in the form of protein, it will not be a problem and your muscles will grow and your health will improve.