Genetic luck: the example of muscle fibers and people

During training we do not often think about how complex the processes are in the body. The benefits of regular physical activity speak for a long time, and every year scientists from around the world trying to shed light on the new "useful" mechanisms of the influence of exercise on health. As a consequence, special attention to active lifestyle, we are scientists gained valuable information about how different processes occur and in what way achieved their jewelry coordination in the human body.

In this article we will try to translate these interesting facts with professional language researchers at popular science and tell simply about difficult.

This time I want to start with the story of the muscle fibers, why in the physiology of their conditionally divided into several types, and what is the difference between strength and aerobic exercise.

Muscle fibers is what is a single muscle, say the biceps. This muscle, like all others, contains two major types of muscle fibers – fast (or white) and slow (or red) .

Myoglobin – protein that binds oxygen in the cells of skeletal muscles and heart muscles and thus provides them with energy for contractions.0

Red fibers, which are located closest to the bone, got its name because of the high concentration of specific cellular organelles – mitochondria("energy plants") and a large supply of pigmented protein of the red color of myoglobin("oxygen carriers").

White (fast) fibers, Red (slow) fibres arethe Source of "fuel" — glycogen (carbohydrate). The reserve "fuel" – subcutaneous adipose tissue [1]. Reduced only in the presence of oxygen.The task of fast fibers is to provide a strong, short cuts with a sharp increase in the activity of enzymes that break down glycogen. Have a great power and the capability of significant growth. The advantage of white fibers in the form of hypertrophy is able to help in the development of power of vozmozhnostyami. Red muscle fibers when high performance is not capable of considerable hypertrophy, i.e. their volume does not increase because of the peculiarities of their metabolism. Responsible for maintaining posture, posture, allow for a long time to run or do 100 reps "on press", but they don't grow. During intensive strength training may be a partial transformation of slow fibers in the intermediate that possess qualities of both slow and fast fibers resulting in increase muscle mass. Stocks red fibers "insured" by the body, and even a sedentary lifestyle are able to maintain these reserves at a level sufficient to move the body in space. Moving to the outer surface of the muscle, you can see the white fibers, which are called so due to the fact that actually have less pronounced color than red. They have few mitochondria, no myoglobin, and to work they need to start the whole cascade of biochemical reactions.

As has become clear, the white fiber is topography, volume and speed-power characteristics. In order to 40 push-UPS or work to the limit, join in fast fibers.

Based on the knowledge about muscle tissue, it is important to understand that, training your endurance during aerobic classes, we mostly zadeystvovany fiber that will "burn fat" and increase the level of metabolism. Force workouts allow you to maintain your muscle tone and shape of the usual muscle features, slender body, using the white fibers.

Now that there is a General perception about the fibers, it's time to learn more interesting scientific facts about muscle tissue.

Everyone knows the popular but obsolete from a scientific point of view, the phrase that nerve cells do not regenerate, but the "irreversibility" refers to the muscle tissue equally.

The fact is that after birth we are not the numerical increase of muscle cells of both types of fibers, and after 35-40 years every year, we permanently lose 1% of lean muscle mass by reducing their volume. To slow down this process helps the active lifestyle and regular yoga exercises training major muscle groups .

Some people, not even bothering to exercise, have enough muscle mass, while others, on the contrary, quickly lose their shape when inactive lifestyle. An explanation for this difference gives genetics, namely the genes ACTN3 and MSTN. Alpha-actinin 3, a protein encoded by the gene ACTN3, which seemed to anchor links actin filaments in muscle and is found only in the white muscle fibers, increasing their contractility and strength .

Actin – contractile protein that makes up about 15% of muscle protein. Connecting with other proteins, the actin fibers acquire the capacity to contract, using the energy contained in ATP. Copies of the ACTN3 GENEHAVE a relatively small number of people this gene is represented by two "working" copies, which they got from each parent. This feature contributes to the high content of ACTN3 in muscle, and, accordingly, high strength, muscle relief, and allows to achieve much success in those sports which require explosive strength or acceleration (e.g., basketball, sprinting and weightlifting). The reverse situation is observed in approximately 18% of the European population when the parents got two "broken" copies of the gene ACTN3. In this scenario white fibers virtually no alpha-actinin 3, these people are mostly red muscle fibers and succeed in endurance sports.The most common situation occurs when one of the parents got a "working" version of the gene, and from another – "non-working", we through training can compensate for the contribution of the "outside" of the gene and to develop speed-strength qualities. In sports genetics research gene ACNT3 allows to identify athletes who can succeed in law enforcement subjects, or in those sports which require a high level of endurance. Also the detection of changes in gene ACTN3 allows to indirectly estimate the ratio of white and red muscle fibers.

In contrast to the effects of the gene ACTN3 is the gene MSTN, which encodes Balochistan. The task of myostatin is to prevent excessive growth of muscle tissue, which is important for heart health.

The NUMBER of GENES of MSTN, there Are times when a person revealed a variant of the MSTN gene having a higher activity, which means that elevated levels of myostatin and, consequently, more rapid confrontation of the body's muscle growth. Such people often asthenic physique, and it is very difficult to build muscle, even combining optimal nutrition with exercise.Rarely, people with two "non-working" versions of the gene MSTN. Of myostatin, they have very little, nothing prevents the growth of muscle tissue, leading to hypertrophy of the muscles without additional workouts. Often they look like bodybuilders because body fat such people have not expressed and manifested muscle relief.Sometimes an intermediate option, when one of the parents, the man went inactive copy of the gene MSTN. Accordingly, the myostatin in the blood contains less due to the protein synthesis with the only working copy of the gene. Such a person easily rebuild muscle and has high strength. Today I covered the two genes for a reason, because they are both responsible for the maintenance of muscle mass.

Only a small portion of people actually prone to a harmonious body and the outstanding opportunities "by nature", and often they become professional athletes. However, most people did not have such obvious advantages in achieving a slender, textured body or develop strength and stamina, so regular exercise like interval and weight help outweigh genetics and lead to noticeable results. It is extremely important to maintain existing muscle tone, protecting them from the inevitable atrophy with age and a sedentary lifestyle. published

P. S. And remember, only by changing their consumption — together we change the world! ©



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