home » Nutrition » Types of muscles. Fast and slow muscle fibers, what is their role in bodybuilding Exercises for slow biceps fibers

Types of muscles. Fast and slow muscle fibers, what is their role in bodybuilding Exercises for slow biceps fibers

Professional bodybuilders and trainers working in gyms know all about fast-twitch and slow-twitch muscle fibers, and can also tell you how they differ from each other. Many amateur athletes are not aware of the classification muscle fibers. Even the few who have heard of it don’t know how to train slow-twitch muscle fibers (SMT) separately? This is exactly the issue we will look into together today.

What are slow-twitch muscle fibers?

Earlier for growth muscle mass Bodybuilders focused on fast muscle fibers, but later scientists found out that slow ones also play an important role in building muscle. Today, experts advise training both types of fibers evenly, although beginners unwittingly focus on fast-twitch fibers.

Slow-twitch muscle fibers are those that have low strength and slow twitch, and their advantage is low fatigue. They are small in size and difficult to hypertrophy.

Physiology is such that slow muscle fibers are responsible for solving the following tasks:

aerobics or dynamic physical activity: long swimming, running, cycling;
production of body heat;
keeping the body in correct position(especially for the back muscles).

Slow-twitch muscle fibers are best developed in cyclists, marathon runners and track and field athletes, for whom physical endurance. This type of fiber contains myoglobin, a special protein that stores oxygen. During aerobic exercise, mitochondria produce energy through the oxidation of glucose under the influence of oxygen. Slow muscle fibers have a better blood supply, so they receive more oxygen compared to myocytes from fast fibers.

Conditions for the growth of slow fibers

To achieve hypertrophy of slow-twitch muscle fibers, you need to slowly perform exercises with relatively light weights (30-50% of the maximum). This explains the effectiveness of pumping, which most professional athletes use in their training. Among the main conditions that are required for training slow muscle fibers are:

Stress. For hypertrophy slow fibers A prerequisite is stress on the muscles, which accelerates the production of hormones. This means that you need to work to failure, causing the destruction of muscle tissue. Restorative processes begin and volumes increase.
Hydrogen ions. They are needed for the development of IMM, and to obtain them you need to exercise until your muscles burn.
Creatine phosphate. This substance is necessary for protein synthesis, so athletes are recommended to take special supplements to increase creatine phosphate levels.
Amino acids. Proteins are built from them, and amino acids can be obtained from food or sports supplements.

How to train correctly to develop slow-twitch muscle fibers?

Let's now find out how to develop slow muscle fibers and how to train for this? The recommendations are quite simple, so everyone can follow them without any problems:

Work with light weights - within 30-50% of your maximum.
Perform all movements as slowly as possible: smooth, slow lifting of the projectile (2-3 seconds), even more leisurely lowering (up to 5 seconds).
Achieve a strong burning sensation in the muscles with each approach and work to failure.
Work within the amplitude, maintaining the muscle in a tense state. For example, when lifting dumbbells for biceps, do not lower them to the very bottom and do not throw them too high so that the muscles at these extreme points do not relax.
Rest little between sets - within 30-40 seconds.
Rest longer between exercises - up to 5-6 minutes or more, if necessary. This is necessary to reduce muscle acidification.
The number of repetitions should be large - 15-20-30, depending on the exercise. The main thing is not the repetitions, but the burning sensation that should be achieved!

Hello! What tricks will the body go to in order to save energy in order to increase our survival. Although, judging by the way the population is growing, sometimes you think that it would be better for him not to do this. Ha ha. But seriously, everything in our body is balanced and optimized. The body will never do anything that is not beneficial to it.

A little about saving energy

As I said, the body does everything to:

Save as much energy as possible(that's why we stock extra energy in the form of fat).
Spend as little energy as possible in any task(that's why we are all lazy by nature).

This allowed us to survive for TENS OF THOUSANDS of years. Our ancestors could enjoy the meat of a killed animal for one week, and then practically starve for two or more weeks, eating only roots (farming appeared later).

Therefore, our body WAS TAUGHT that in order to survive in the harsh conditions of natural selection (predators, diseases, hunger, etc.) IT IS NECESSARY TO SAVE THE ENERGY RECEIVED!

He does this whenever possible, for example:

Nutrient accumulation system (we store excess food in fat and do not remove it from the body);
Muscular adaptation (muscles will not grow without increasing the load, i.e. without a STRONG need to warn yourself from danger);
Hair on the body, calluses on the hands from constant work, tanning from the sun (even this was done to save energy, since this is also a forced adaptation to external influences);

The body adapts ONLY WHEN NECESSARY, such as: “It’s better to grow hair on your body than to freeze from the cold,” “It’s better to grow calluses on your hands than to get blood poisoning and die,” etc. It won’t do this if you don’t care. need to! It SAVES ENERGY!

What can I say, EVERYTHING IN OUR BODY IS MADE TO SURVIVE BETTER IN THE ENVIRONMENTAL CONDITIONS! If the body can save energy somewhere, it will do it! Therefore, it is always more convenient for us to walk than to run; stand rather than walk; sit rather than stand; lie down, rather than sit, etc.

As you probably already understood, LAZINESS- This is also an ADAPTATION MECHANISM of the body to save energy.

It was in order to save energy that our body created another amazing mechanism - different types of muscle fibers.

In order to save energy, muscle fibers in our body are heterogeneous.

What's the point of dividing our muscles into different types muscle fibers? VERY BIG!

Look, as a rule, in life we have different types of physical activity, namely:

Very heavy (for example, you need to move a very heavy piano).
Medium in weight, high-volume (for example, carry a lot of medium-heavy bags of potatoes).
Easy (long, monotonous run).

Is it beneficial for our body, for example, to use the ENTIRE HUGE MUSCLE MASS OF THE LEGS for a light load? Naturally, NO!

It is for this purpose that our body has created “different workers” to perform work of different types.

Fast-twitch muscle fibers (FMTs).
Slow-twitch muscle fibers (SMF).

But! There are also fibers that are designed to perform EXTREMELY HEAVY WORK, namely HIGH THRESSION fast muscle fibers (HFTF).

Those. we get three main types of muscle fibers:

To more clearly imagine the situation, why the body needed such transformations, imagine that our ancestors were going hunting.

Here they are slowly moving through the forest and, in their opinion, are in complete control of the situation. AND SUDDENLY a PREDATOR – A SABER-TOoth TIGER – jumps SHARPLY out of the bushes at one of them!

The man is SCARED TO DEATH and in a split second he jumps to the side so as not to die. At this moment, HIGH-THRESHOLD FAST MUSCLE FIBERS, which were created to perform extreme work and to respond instantly, were activated.

But the predator does not give up and begins to run after the Cro-Magnon man. This is where FAST MUSCLE FIBERS come into play, allowing you to gain fast speed in short time!

But the predator does not give up and continues to pursue the unfortunate bare-assed hunter. After a certain time, the hunter’s body understands that it will take a long time to run and turns off fast muscle fibers, while connecting SLOW MUSCLE FIBERS to perform monotonous, long work (running).

Well, to hell with it, let there be a happy ending. The man ran to the cliff and jumped into a deep river and swam away to his fellow tribesmen.

That's how it is, guys. Got it? During physical activity, our body does not use all the fibers of the working muscles at once., but uses only those that are necessary for him to perform SPECIFICALLY GIVEN TYPE OF WORK! And all because this way he can save more energy. Part of a muscle spends less energy than the entire muscle! Elementary.

I want to make one caveat. Endurance fibers can be either fast-twitch or slow-twitch muscle fibers, and fast-twitch fibers can be both durable and easily fatigued.

However, for ordinary people who play sports at an amateur level or who do not play sports at all, this will be exactly the case. MMVs are likely to be more durable than BMWs, because... they will have much more mitochondria and mitochondrial enzymes.

Mitochondria, in turn, are capable of obtaining “energy” from the oxygen (respiration) and reagents (fats or pyruvate) at their disposal as a result of chemical transformations - the same ATP that provides almost all energy-consuming processes in our body.

The purpose of different types of muscle fibers

Let's take a closer look at the different types of muscle fibers. So:

High-threshold fast muscle fibers (HTF)– designed for VERY HEAVY WORK and QUICK INCLUSION into work with SUBMAXIMUM weight. They use fast energy sources for their contraction, which are capable of rapid resynthesis (creatine phosphate and glycolysis). When an athlete lifts a barbell with weight 1 time, i.e. 1 repetition maximum (RM), then all this is the work of HIGH THRESHOLD BMWs. To prevent you from breaking yourself, nature came up with a similar mechanism, a “quick response team,” if you like. These fibers are very strong and WHITE.
Fast-twitch muscle fibers (FMT)– designed to perform HEAVY and HIGH-VOLUME work with MODERATE-HEAVY WEIGHT (6-12 repetitions). They are used for reduction, just like VBMW, fast sources of energy. These fibers are also called WHITE and they are used by all athletes of speed-strength sports (BB including).
Slow-twitch muscle fibers (SMF)– they are designed to perform light, long, monotonous work. Perform SLOW and LIGHT contractions. Therefore, they use slower but more economical energy sources. One of these is OXIDATION OF FATS WITH THE HELP OF OXYGEN. This provides noticeably more energy than glycolysis, but requires more time, because The oxidation reaction is very complex and requires a lot of oxygen, which is why MMFs are called RED MFs (because oxygen is carried by hemoglobin, which gives the fibers their red color). These are the fibers that are primarily used by marathon runners, cyclists, etc.

So, should you even bother training other muscle fibers?

Do you need to train all muscle fibers?

If you are a beginner bodybuilder, then PROBABLY NOT! Your body is not yet accustomed to the load and has not even learned , designed for such work FAST MUSCLE FIBERS.

BUT! If you have already been working out in the gym for 2-3 years and have stagnated in the results, then training slow muscle fibers can cause very good progress!

It would seem that if a person runs marathons, then it is logical for him to train IMM, and if he works with very heavy scales, then BMW and VBMW. But it's not that simple, friends.

Body-building- a very specific sport where all means are good to achieve maximum performance (from training different types of muscle fibers and microperiodization to the use of very large doses of pharmacology).

ONE WHOLE IS ALWAYS BIGGER AND STRONGER THAN A PART! If we develop all the muscle fibers, then it is logical that the muscle will be larger overall.

Previously, it was believed that there was no point in training IMM. The fact is that when a BIOPSY (sample of a small part of the muscle) was taken from athletes of Olympic sports (weightlifting, sprinters, javelin throwers, etc.), they noticed that, as a rule, there are many times more fast muscle fibers, than slow ones. Therefore, they said that you need to train fast-twitch fibers and “don’t sweat it.” The research was closed.

But what was the surprise of the men in white coats when, after some time, they took samples muscle tissue from professional bodybuilders! THE NUMBER OF FAST AND SLOW MUSCLE FIBERS WAS THE SAME!

After additional experiments, scientists concluded that SLOW MUSCLE FIBERS GROW AS WELL AS FAST FIBERS!

Why do bodybuilders' results differ from other athletes?

The difference is in the goals. IN Olympic sports they are different sports. Run faster, push more, throw further, etc. And in bodybuilding, volumes, proportions and appearance are important.

Therefore, it is important for Olympians to minimize muscle growth, including IMM. They need fast or high-threshold muscle fibers in order to make maximum effort at the right moment.

Okay, you might say, why then don’t marathon runners, who need slow-twitch muscle fibers, have huge, toned legs? It's all about the MMV training method, friends.

Method of training MMV. Blood acidification

First, a little theory. With all the current technical and other progress, we still DO NOT KNOW WHAT EXACTLY TRIGGERS MUSCLE GROWTH!

But what about the progression of loads, stress, anabolic hormones, amino acids, etc., you ask? Yes, and again, yes! Only these are only the FINAL MECHANISMS OF MUSCLE GROWTH.

But we know for sure that NEW PROTEIN SYNTHESIS IS TRIGGERED THROUGH THE CELL'S DNA.

In order for hormones to trigger protein synthesis, this information must be copied from the DNA of the cell nucleus. And the DNA chain itself, as we know, is twisted from two helices.

To start protein synthesis YOU NEED TO UNLOCK THE DNA HELIDS! How to do it? With the help of HYDROGEN IONS!

Pumping– this is, roughly speaking, pumping blood into muscles. But remember what pumping should be like, in the classical sense? I won’t bore you, he must be STRONG! Those. approximately 80% of WORKING WEIGHT!

For example, if you bench pressed a 100 kg barbell 6-8 times, then for a pumping workout you need to lift 80 kg and perform 12-15 repetitions. Do you understand? This will pump blood into the muscles, but this is not exactly the mode of operation that is aimed at developing IMM.

Add to this the fact that in pumping training, as a rule, the approach is performed at a FAST PACE! And for the fast pace of movement we have created BMWs.

MMB should be trained with approximately 50% weight and at a VERY SLOW pace! But more on that later.

Let's return to the question, why are marathon runners running long distances, do not have large slow-twitch muscle fibers? After all, they directly train them!

There are two factors here:

No load progression. Although the load is light and monotonous, it must grow, otherwise there will be no point in the muscles increasing.
No muscle acidification. Yes, they work for a long time, with a lot of repetitions (thousands of steps), but the BLOOD CIRCULATES FREELY IN THE MUSCLES (in and out), so it washes away the hydrogen ions. Accordingly, there is no growth reaction.

How to make MMV grow?

Although MMF grow no worse than BMW, in order for protein synthesis to start in muscle fiber (any muscle fiber, even MMF), the presence of HYDROGEN IONS is necessary, which trigger it.

It is easier for fast muscle fibers to achieve this, because. for energy supply they use the ANAEROBIC (oxygen-free) method. Therefore, the blood (the instrument for transporting oxygen to the muscles) DOES NOT WASH AWAY THE HYDROGEN IONS, which are needed to trigger muscle growth.

Why is this more difficult to do in MMV? Because MMVs use an AEROBIC (oxygen) method of energy supply! This means that blood is needed to transport oxygen. Do you understand? Blood makes it possible to feed on oxygen (deliver it), but WASHES AWAY HYDROGEN IONS, which are needed for growth! Here is a vicious circle that does not allow MMV to grow under normal conditions.

To put it simply, “native” methods of energy supply allow BMW to grow, but do not allow MIW to grow!!! This is why marathon runners have small muscles.

All this is understandable, but how to get out of this vicious circle and pump up our slow muscle fibers to become 2 times larger?

Make MMV work;
Use another method of energy supply;

Those. a certain load is needed to TURN ON the MMV, but NOT TO RELEASE BLOOD FROM THE MUSCLE in order to acidify it!!!

How to do it? PUMPING, friends! But in a slightly different mode.

Optimal pumping mode

In bodybuilding, a dynamic (fast) mode of performing the exercise is usually used, and relaxation follows after each repetition.

In this mode, the vessels unclench and allow blood to circulate freely into and out of the muscle. This is bad for the growth of IMM, because... they need HYDROGEN IONS to grow, and the blood washes them away. The muscle does not acidify and the muscle mass does not grow (there is no increase in strength and mass).

Therefore, the classic pumping mode, i.e. DYNAMIC POWER IS NOT SUITABLE FOR US!

We need to use CONSTANT MUSCLE TENSION! After all, if a muscle is tense, it does not allow blood to pass through. This is good because... this contributes to the accumulation of HYDROGEN IONS in it!

HYPOXIA(no oxygen due to constant voltage) –> ANAEROBIC GLYCOLYSIS(breakdown of glucose without oxygen) –> Accumulation of HYDROGEN IONS.

Great. That's sorted out. Again. The muscle should not allow blood to pass through (constant tension), anaerobic glycolysis occurs (no air), so hydrogen ions accumulate (since blood and oxygen do not circulate).

Now let's look at what the conditions should be for MMV hypertrophy.

Practical scheme for MMV hypertrophy

What we need for maximum hypertrophy (“swelling” of muscle cells):

Let's look at this using the example of a standing biceps curl.

For example, your working weight is 30 kg for 10-12 reps, and you lifted 40 kg for 1 rep (40 kg is your 1 rep max). PM is a repeated maximum!

How to proceed?

First we select the weight based on our 1RM. We take 30-50% of it, i.e. from 40 kg, it will be 12-20 kg.
Now, by bending our elbows, we remember our starting position. THE HANDS SHOULD NOT BE COMPLETELY EXTENSION during the approach to avoid bleeding. We work INSIDE the amplitude! Those. we do not reach the top and bottom points. As soon as we feel that the muscle can relax, we stop and move in the opposite direction.
Raise and lower the barbell VERY SLOWLY! On the count 1-2 up and 3-4 down! If possible, even slower! This is how we use our MMVs and turn off the BMWs from operation.
WE ACHIEVE AN UNBEARABLE BURNING! This is very important point. It must be so strong that it can raise this very a light weight Once again, it is simply not possible. We reach muscle failure. This will indicate extreme acidification of the muscle, i.e. about the high content of HYDROGEN IONS. There will be more repetitions than usual, namely 20-30 and the approach will last 30-50 seconds. This is fine!

This is what one approach would look like. How many approaches should there be? In theory, A LOT, but we, as you know, , so let's look for a solution.

To reduce the burning sensation we need about 5 minutes, and for it to disappear completely we need 40-60 minutes.

Therefore, based on the above, it would be optimal to perform such approaches every hour throughout the day. But this will be convenient for few people.

I prefer to use the STEP METHOD of muscle acidification. Those. you perform 3-4 approaches with MINIMUM REST, then rest for 3-4 minutes and again repeat 3-4 approaches, so again rest 3-4 minutes and again the series.

Example: You completed a biceps curl in 30 seconds. Rest for 20-30 seconds and repeat the second set, now rest again for 20-30 seconds and perform the third set. Now rest for 3-4, or maybe 5 minutes. And repeat a series of 3 approaches with a break of 20-30 seconds. Such “series” can be done from 2 to 5 within one workout.

AN APPROACH(30-50 sec) + REST(20-30 sec) + AN APPROACH(30-50 sec) + REST(20-30 sec) + AN APPROACH(30-50 sec) + REST (3-5 minutes!) … REPEAT SERIES…

By the way, this is convenient because many exercises can be performed at home (push-ups, biceps, triceps, deltoids).

Conditions for muscle growth

So, what does it take to grow muscles?

TRAINING STRESS (destruction)! It is needed to promote the production of ANABOLIC HORMONES! Only then will the body turn on the growth process (anabolism).
HORMONAL BACKGROUND! We need HORMONES that copy information about protein synthesis from the cell's DNA. It is thanks to them that metabolism (metabolism) shifts towards growth (anabolism). The destruction of protein structures during training forces the body to repair the damage. This healing is precisely called PROTEIN SYNTHESIS.
HYDROGEN IONS! We have already talked about them quite a lot today. They UNCOIL the DNA helix so that information about protein synthesis becomes available for reading by hormones (steroid-receptor complexes). If there are not enough hydrogen ions released in response to ATP consumption, then hormones will not have the opportunity to read information about protein synthesis and trigger growth. REMEMBER: HORMONES (steroids) without training stress WILL NOT GIVE RESULTS, but TRAINING WITHOUT HORMONES WILL!
CREATINE PHOSPHATE! Gives energy to the DNA molecule for fast work. Also, supplementing with CREATINE MONOHYDRATE can help you complete an extra couple of reps in your workout. A good thing.
AMINO ACIDS for growth! In order to grow muscles, you need something to grow from! Amino acids are plastic building materials for muscle growth.

Yes, protein (amino acids) is very important! But more in conditions of DIET (deficiency of simple carbohydrates). Imagine when you are losing weight, i.e. If you don’t eat carbohydrates and exercise, then there is VERY LITTLE glycogen in your muscles, which means you have to use amino acids as energy (an expensive source of nutrition). If you drink extra during training and after amino acids, you will retain more muscle.

This is not beneficial for manufacturers sports nutrition, because PROTEIN IS MORE EXPENSIVE and you can get MORE from its sale! But I believe that it is so. CARBOHYDRATES ARE MORE IMPORTANT than protein, especially when gaining muscle mass, because... give energy to your muscles.

The fact is that after training, your body DOESN'T EVEN THINK about growing muscles, because... it has depleted its energy reserves! He needs to make up for them! That is why for the next two days after training, your body replenishes energy reserves and does not even think about growth. And contractile proteins continue to be destroyed by enzymes - PROTEIN KINASES! Only after 2 days the body starts recovery and, as is usually written, it recovers in 7 days. But in fact, even more. Usually within 10-14 days.

Let's summarize:
TRAINING STRESS(destruction).
HORMONAL BACKGROUND(starting synthesis from DNA).
HYDROGEN IONS(unwinding of the DNA helix for hormones).
CREATINE PHOSPHATE + CARBOHYDRATES(energy supply).
AMINO ACIDS(building material for plastic structures).

This applies to ANY muscle fibers (MMV, BMW, VBMV). The only difference is that for MMV it is more difficult to maintain the required concentration of hydrogen ions, so it is necessary to perform the exercises in a certain way, as we discussed earlier in this article.

Is it possible to combine MMV and BMW training?

Can. I'll tell you more. That's exactly what I did in the army. I remember that I once trained my arms so much that I couldn’t button up my jacket in the morning; my colleagues helped me, because... they were unbearably sick! That's what it means, I've never trained MMV.

There are several basic rules:

WE ALWAYS TRAIN AFTER BMW(if you train them in the same workout).
MMV RECOVER SMALLER(2-3 days, i.e. already on the third day you can train again).
BMW + 1-2 days of rest + MMV(if you train in different workouts).

Example training program No. 1 (ALTERNATING WEEKS):
BMW week (80-90% of 1 RM, 6-8 reps, fast pace, failure);
week IMM (30-50% of 1 RM, 30-50 sec approach, constant tension, failure);
Recovery week (50%, 8-12 reps, no failure);

Example of training program No. 2 (BMW + MMV in one training session):
BMW Week + MMV;
Recovery week (or very light training with 50% weight NOT TO FAILURE);

OK. But how can we combine MMV and BMW training in practice?

Example of a combination (BMW + MMV in one training session):
BMW– Bench press incline bench : 4 sets (80 kg x 6-12).
BMW– Incline dumbbell press: 4 sets (30 kg (1 dumbbell) x 6-12).
BMW– Dumbbell flyes lying on a bench: 4 sets (20 kg (1 dumbbell) x 8-12).
MMB – Incline Bench Press: 2-3 x ((30 kg = 30-50 sec. approach + 20-30 sec. rest) x 3 sets + rest 3-5 minutes + REPEAT SERIES...).
MMV– Incline Dumbbell Press: 2-3 x ((10-15 kg (1 dumbbell) = 30-50 sec. approach + 20-30 sec. rest) x 3 sets + rest 3-5 minutes + REPEAT SERIES...).

Do you see what's funny? We always download BMW at the beginning, before MMV! MMV IS ALWAYS IN THE END! UNDER NO EVENT CAN YOU CHANGE PLACES!

If we trained two muscle groups in one workout, for example, CHEST + ARMS, then we would first need to train the BMW CHEST, then the BMW ARMs, and only THEN the MIB CHEST + MIB ARMs. Just as you can see, WE TRAIN THE LARGE MUSCLE GROUPS FIRST (legs, back, chest), and only then the SMALL MUSCLE GROUPS (delts, arms, calves).

RIGHT= BMW Chest + BMW Arms + MMV Chest + MMV Arms.

WRONG = BMW Chest + MMV Chest + BMW Arms + MMV Arms.

WRONG= BMW Arms + BMW Arms + BMW Chest + BMW Chest.

I guess I’ll end this article here. If you are a beginner, then you DO NOT NEED this for now, but if you are already an experienced athlete who has been training for two years and has stagnated in results, then IMM training can be a very good help in achieving new horizons in muscle growth.

P.S. Subscribe to blog updates. It will only get worse.

With respect and best wishes,!

Skeletal muscle fibers are divided into fast and slow. The speed of muscle contraction varies and depends on their function. For example, it shrinks quickly calf muscle, and the eye muscle contracts even faster.

Rice. Types of muscle fibers

IN fast muscle fibers the sarcoplasmic reticulum is more developed, which contributes to the rapid release of calcium ions. They are called white muscle fibers.

Slow muscles are constructed from smaller fibers and are called red fibers because of their reddish color due to their high myoglobin content.

Rice. Fast and slow muscle fibers

Table. Characteristics of three types of skeletal muscle fibers

Index	Slow oxidative fibers	Fast oxidative fibers	Fast Glycolytic Fibers
The main source of ATP formation		Oxidative phosphorylation	Glycolysis
Mitochondria
Capillaries
	High (red muscles)	High (red muscles)	Low (white muscles)
Glycolytic enzyme activity		Intermediate
		Intermediate
Fatigue rate	Slow	Intermediate
Myosin ATPase activity
Shortening speed	Slow
Fiber diameter
Motor unit size
Motor axon diameter

Muscle strength

The strength of a muscle is determined by the maximum amount of load it can lift, or by the maximum force (tension) it can develop under isometric conditions.

Single muscle fiber capable of developing a force of 100-200 mg. There are approximately 15-30 million fibers in the body. If they acted in parallel in the same direction and at the same time, they could create a voltage of 20-30 tons.

Muscle strength depends on a number of morphofunctional, physiological and physical factors.

Calculation of muscle strength

Muscle strength increases with increasing area of their geometric and physiological cross-section. The physiological cross-section of a muscle is the sum of the cross-sections of all muscle fibers along a line drawn perpendicular to the course of the muscle fibers.

In a muscle with parallel fibers (for example, the sartorius muscle), the geometric and physiological cross-sectional areas are equal. In muscles with oblique fibers (intercostal) the physiological cross-sectional area is larger than the geometric area and this helps to increase muscle strength. The physiological cross-section and strength of muscles with a feathery arrangement of muscle fibers, which is observed in most muscles of the body, increase even more.

In order to be able to compare the strength of muscle fibers in muscles with different histological structures, the concept of absolute muscle strength is used.

Absolute muscle strength — maximum strength, developed by the muscle, calculated per 1 cm 2 of physiological cross-section. The absolute strength of the biceps is 11.9 kg/cm2, the triceps brachii muscle is 16.8, the gastrocnemius muscle is 5.9, and the smooth muscle strength is 1 kg/cm2.

where A ms is muscle strength (kg/cm2); P is the maximum load that the muscle can lift (kg); S is the physiological cross-sectional area of the muscle (cm2).

Force and speed of contraction, muscle fatigue depends on the percentage various types motor units included in this muscle. The ratio of different types of motor units in the same muscle varies from person to person.

The following types of motor units are distinguished:

slow, tireless (red), they do not develop great strength contractions, but can remain in a state of tonic tension for a long time without signs of fatigue;
fast, easily fatigued (white in color), their fibers develop great contraction force;
fast, relatively resistant to fatigue, developing a relatively large force of contraction.

In different people, the ratio of the number of slow and fast motor units in the same muscle is determined genetically and can vary significantly. The greater the percentage of slow fibers in a person’s muscles, the more adapted it is to long-term, but low-power work. Individuals with a high content of fast, strong motor units in their muscles are able to develop greater strength, but are prone to fatigue quickly. However, we must keep in mind that fatigue depends on many other factors.

Muscle strength increases with moderate stretching. One explanation for this property of muscle is that when the sarcomere is stretched moderately (up to 2.2 μm), the likelihood of more connections between actin and myosin increases.

Rice. Relationship between contractile force and sarcomere length

Rice. The relationship between muscle strength and its length

Muscle strength depends on the frequency of nerve impulses, sent to the muscle, synchronizing the contraction of a large number of motor units, preferentially involving one or another type of motor units in the contraction.

The strength of contractions increases:

when more motor units are involved in the contraction process;
when synchronizing the contraction of motor units;
when more white motor units are involved in the contraction process.

If it is necessary to develop a small force, the slow, non-fatiguing ones are activated first. motor units, then fast, fatigue-resistant. If it is necessary to develop a force of more than 20-25% of the maximum, then fast, easily fatigued motor units are involved in the contraction.

At a voltage of up to 75% of the maximum possible, almost all motor units are activated and a further increase in strength occurs due to an increase in the frequency of impulses sent to the muscle fibers.

With weak contractions, the frequency of sending nerve impulses along the axons of motor neurons is 5-10 impulses/s, and with a strong contraction force it can reach up to 50 impulses/s.

In childhood, strength increases mainly due to an increase in the thickness of muscle fibers, which is associated with an increase in the number of myofibrils in them. The increase in the number of fibers is insignificant.

When training muscles in adults, an increase in their strength is associated with an increase in myofibrils, and an increase in their endurance is due to an increase in the number of mitochondria and the production of ATP due to aerobic processes.

There is a relationship between the strength and speed of muscle contraction. The greater the length of a muscle, the greater the speed of muscle contraction (due to the summation of the contractile effects of sarcomeres). It decreases with increasing load. A heavy load can only be lifted by moving slowly. Maximum speed contraction achieved when human muscles contract is about 8 m/s.

Muscle power equal to the product muscle strength on the speed of shortening. Maximum power is achieved at average speed muscle shortening. For the arm muscles, maximum power (200 W) is achieved at a contraction speed of 2.5 m/s.

The force of contraction and muscle power decrease as fatigue develops.

In this article, I will tell you how and why to train SMT (slow twitch muscle fibers).

In short, there are fast twitch muscle fibers and slow twitch muscle fibers. If the goal is to develop maximum muscles, you need to train both the BMW and the SMV, because the ongoing studies of scientists who took BIOPSY samples from professional athletes have proven that the MMF have reached the same level as the BMW, respectively, slow muscle fibers (SMF) have no less potential for than fast muscle fibers (FMT).

In most cases, people involved in gym Only BMW develops. They may not know this)), but it is so. In this way, they limit their possible potential... In order to include the IMM in the work, specific training is required, which I will talk about below.

Slow-twitch muscle fibers (SMF) are designed to perform slow (logical) and light (weight-bearing) contractions.

Accordingly, in order to develop IMM, you need to perform the exercise with light weights (30-40% of the weight for one repetition maximum) at a very slow pace. That's actually the whole secret)). However, this is just the tip of the iceberg. There are many more extremely important nuances that need to be taken into account. About them below!

CONDITIONS FOR MMV GROWTH:

Exercises are performed with light weights (30-40% of 1 RM), otherwise BMWs will work...
The exercises are performed at a very slow pace (raising 2-3 seconds, lowering 3-5 seconds, or even slower);
In each set of exercises, you need to achieve a hard burning sensation in the muscle +.
When performing exercises, you should try to work as if “within the amplitude”, so that the working muscle is constantly tense (so that the load does not leave the working muscle), this will allow you to achieve the point above, i.e. severe burning + refusal.
The rest between sets of exercises is very short: no more than 30 seconds.
The rest between exercises is long: 5-10 minutes. This is exactly how long it takes for a muscle to significantly reduce acidification. Although, it is worth mentioning that complete acidification in the muscle returns to its original level after 30 -60 minutes (this explains why some athletes train MW literally all day, every hour, one exercise, but this scheme is not suitable for most people , because who has the opportunity to train stupidly all day...).
The number of repetitions is large: you don’t even have to count, the main thing is to achieve a severe burning sensation in the muscle + muscle failure. Usually this is about 20-30 repetitions per approach.
The number of approaches is also large: (minimum 3, preferably from 5, you can go up to 10 in one exercise);

Is it possible to combine MMV training with BMW? If yes, then how.

Can. I could even say it is necessary, because this is very, very reasonable from the point of view of muscle hypertrophy (growth), however, in any case, you need to look at each situation individually.

2 (two) reasonable (from my point of view) options for combining BMW and MMV training:

ALTERNATION OF WEEKS: 1 week - BMW; 2nd week - MMV; (there’s no need to even explain everything here)

At one training session: first - BMW, and after - MMV.

P.s. if you want to train both BMW and MMV in one training session, remember the basic rule: train BMW first, and only then MMV. ON THE CONTRARY - IT IS IMPOSSIBLE!!!

This is extremely important!!! For example, if you work out 2 muscle groups during training (for example, chest + back), then first you must perform all the exercises you need for the chest and back = BMW, and only then necessary exercises on the chest and back = MMV.

Example (chest + back workout):

BMW: Wide (medium) grip pull-ups to chest
BMW: Bent-over row
MMV: Incline bench press
MMV: Traction vertical block to the chest

P.s. On my own behalf, I will say that combining BMW and MMV training in one training session is quite difficult, because there are a lot of exercises and a lot of approaches, in the end it’s difficult to fit into a workout of no more than 45 minutes (well, when 2 muscle groups are allowed to last up to 1 hour, no more). After all, who doesn’t know power training for straight people it should last exactly that long. More details in the main article: If you fit in, then everything is ok, go for it.

If alone muscle group for a workout (for example, there is a chest), then first all the necessary exercises = BMV, and only then the necessary exercises = MMV.

Example (chest workout):

BMW: Incline Bench Press
BMW: Incline Dumbbell Press
BMW: Push-ups
MMV: Incline bench press 3-5 sets x 20-30 reps = rest between sets no more than 30 seconds.
break between next exercise 5 minutes;
MMV: Incline dumbbell press 3 X 20-30 / rest between sets no more than 30 seconds.

In principle, you can train MMV without combining it with BMW

This is also possible. But, just like that (from the bay of floundering - I would not recommend it). Training only MMV, completely excluding BMW just like that = not reasonable. It makes more sense to combine BMW + MMV.

MMV without BMW is possible only during certain time periods (not suitable for everyone).

For example, only MMV without BMW is completely possible after! Now I had a knee injury, I hadn’t trained for about 3 weeks, and I decided to give myself a so-called. MACRO-PERIODIZATION (since it’s high time, this is just the ideal case). For those who don’t know, macro-periodization is when you start with light weights and gradually progress to maximum ones.

So, I will start my training with MMV training (only them, without BMW). This will be reasonable, because... MMV just means light working weights (that’s what I need), at the same time I’ll tighten it up, let’s say)). Then, after, for example, a MONTH, I think during this time I will “get involved” in the training - I will begin to gradually increase the weights, and as soon as I reach the middle (middle weights) - I will finish working on the development of IMM, and start working on. After hyperplasia - I’ll go further, I’ll start progressing until maximum weights, thereby starting to train the BMW.

Do you understand the point? With all this - I show YOU how you can INDIVIDUALLY tailor the training of something to YOURSELF! Those. the main thing is to understand how this is done. If you don’t understand, it’s better to just combine BMW + MMV (either alternate weeks, or in one workout, whichever is more convenient for you).

Basically, he said everything he wanted. I hope everything is accessible and understandable. Take heart, friends. All the best)).

Best regards, administrator.

Salute, friends! The topic of this material is quite meaty. I think it might appeal to fans of Moscow Spartak (not a fan myself) or residents of Poland. Now we'll talk about reds and whites. True, we will not discuss the civil war of almost a century ago, but muscle fibers.

First, let's look a little deeper into our multi-component body. Let's imagine that we have the opportunity to see everything that happens under our skin. I’m sure the spectacle will shock many :) But let’s not use too much imagination, let’s focus exclusively on muscle mass. If our eyes had a built-in X-ray vision function, then when we looked at our muscles, we would see a fairly multi-colored picture. The fact is that some of our muscle fibers have a more pronounced red color, while the other part cannot boast of such a rich shade.

Surely you have already guessed that the difference in color means difference in type among the variety of muscle fibers, which in the modern world are usually divided for white and red. There are also transitional types, but we will not touch on them so as not to bother our heads. By the way, the difference in color is not so interesting to us. It is provided by a higher concentration of myoglobin (oxygen-binding protein) in red muscle fibers. Much more important for us physiological purpose every type of fiber in our muscles. This parameter is perfectly revealed in an alternative version of the division of muscle components into fast and slow muscle fibers. Let's talk a little more about each type.

White and fast

Fast-twitch (white) muscle fibers (FMTs) use an oxygen-free (anaerobic) method of energy supply. This is the same type of metabolism that is responsible for the explosive and short-lived actions performed by our body. You don’t need to look far for examples of such actions. Classic bodybuilding principles, which advocate working in the 6-12 repetition range, are aimed specifically at developing this type of fiber. Another good example is sprint running. In both cases, the body receives a short (within 10-20 seconds) and intense load at the limit of one's capabilities (work in failure).

In addition to color, fast muscle fibers characterize large fiber diameter, high glycogen content, high speed contractions, fatigue and maximal strength. But the most important thing for us is that this type characterizes greatest ability to hypertrophy (in Russian - muscle growth). That is why the main task of most bodybuilders of all times is the active development of BMWs, which, as a result of a certain load, are capable of increasing in cross section. You are well aware of this load; most likely, you use it when working out in the gym.

Red and slow

Slow-twitch (red) muscle fibers (SMF) use oxygen (aerobic) method of energy supply. As has already been said, this type fibers are saturated with myoglobin, which stores oxygen molecules. Well, while performing aerobic exercise physical activity energy is produced by oxidation of glucose with oxygen(that's why it's oxygen). This type of metabolism begins to occur when continuous and long-term work.

Moreover, the duration of the load can vary from literally 30 seconds, up to several hours, during which, for example, marathon runners run their killer distance. The main characteristic of slow fibers is their high endurance, which white fibers never dreamed of. Accordingly, much more is needed to pump them up.

By analogy with fast muscle fibers, slow muscle fibers have a number of features. They have smaller fiber diameter, low glycogen content, slow contraction rate, low fatigue and low strength. As for the ability to hypertrophy, the opinions of analysts are divided. Some say that red fibers are practically incapable of growth, others argue that their anabolic potential is no less than that of white fibers. In this controversial issue, everyone is right in their own way, but we will try to find golden mean.

Features of training

First, let's look at the proposed slow-twitch fiber training scheme, designed to activate the coveted muscle hypertrophy. This type of training is usually called “pumping” - from the English pump - to pump. As a result of using this training technique, the muscles are abundantly filled (pumped) with blood, and the concentration of lactic acid reaches the limit, causing an unbearable muscle burning. This effect is achieved by working with small weights in a shortened amplitude, and the range of repetitions on average lies in the range from 20 to 30. The technique is tempting, because it allows you to abandon the prohibitive weights on the bar, minimize the likelihood of injury and focus on technique. But will this approach work? Let's return to the debate about the possibility of growth of red fibers.

The world of modern professional bodybuilding knows thousands of examples where athletes managed to build up serious muscle volumes by working with relatively small weights. a large number of repetitions. It turns out that MMVs are indeed capable of serious growth. It’s difficult to argue with this, because there are indisputable facts. But let's take a look at the other side of the moon, which, unfortunately, few people want to look at. Successful examples of the development of red fibers in most cases are found in professional environment of athletes. Among amateurs, such examples are rare, despite the fact that pumping is actively promoted and used quite massively by newly minted athletes.

What distinguishes an amateur from a professional in bodybuilding, and in most sports, besides attitude? Let's play in the Field of Miracles? There is a word of 12 letters. I allow you to open any 4 letters. Let's imagine that it turned out f*r****l***ya. Will you say the word right away or will you spin the drum?

The "course" sector on the drum! That's right, this word is Pharmacology! A real pro is distinguished by huge dosages of a variety of drugs from A to Z. An amateur has the right not to use steroids or other types of doping at all.

It is athletes who actively use anabolic substances that have success in the development of slow muscle fibers. A natural bodybuilder has only one right path at a fork in the road. muscle growth- This development of fast fibers. Don't believe me? Check it out for yourself! I will only be glad if you can prove otherwise!