A muscle group is a group of muscles consists of several muscles that perform the same function. That is, when performing any of the same type of movement, the entire muscle group is immediately included in the work.
Variesties of muscle groups
Muscle groups are subdivided into:
1) Chest muscles
2) The muscles of the shoulder girdle
3) Arm muscles
4) Back muscles
5) Leg muscles
6) Abdominal muscles
The largest of these muscle groups are the muscles of the legs and back, the smallest are the muscles of the arms and shoulders.
Let’s take a look at each of these muscle groups separately:
The muscles of the chest are subdivided into:
1) the pectoralis major muscle which, in turn, is divided into the upper, middle and lower bundles. The middle and lower bundles are the largest and they are often the most developed in an athlet body. The upper bundle of the pectoral muscles is small in size; in most athletes, it lags behind. This is due to the fact that when performing the most popular exercise for developing chest muscles – the bench press, the upper beam receives an extremely small load. This is corrected by bench presses at positive angles (20, 30, maximum 45 degrees).
2) the pectoralis minor which is located under the pectoralis major muscle.
3) the serratus anterior muscle which is located just below the lower bundle of the pectoralis major muscle. These muscles are negligible in size, so most often athletes do not increase their volumes, but work on definition.
The muscles of the shoulder girdle, or as they are also called deltoids, are divided into:
1) The front bundle of deltoids is the smallest of those presented, and often the most developed in athletes. This is due to the fact that almost all presses (lying / at an angle or sitting) load it in one way or another.
2) The medial bundle of deltoids is the largest of the presented ones. The hallmark of any bodybuilder is wide and large shoulders. The medial deltoid gives volume and roundness to the deltoid muscles on the whole. Therefore, pay your attention on training this part of shoulders.
3) The rear bundle of deltoids is the average size of those presented, and often the least developed in athletes. Because of its location, bodybuilders often have no deal with it and train rarely or not in full, but in vain. A well-developed rear bundle of deltoids not only gives aesthetics to your back, but to some extent will displace and raise the medial bundle of deltoids, which will make your shoulders visually even more massive.
The muscles of the arms are divided into:
1) Biceps are located on the front of arms between the shoulder and elbow joints. The most favorite muscle of 99% of athletes, therefore, it is often the most developed among the muscles of the arms. The biceps consists of two heads – long (located on the inner surface of the arm) and short (located on the outer surface of the arm). Also, the brachialis can be attributed to the biceps. A small muscle located under the short head of the biceps. The development of the brachialis leads to the displacement and rise of the short head, which makes the biceps visually more massive.
2) Triceps are located on the back of the arms between the shoulder and elbow joints. The triceps consists of three heads: long, lateral and medial. Triceps is included in all presses to one degree or another, so it is well developed for most athletes.
3) Forearm. The muscles of the forearm consist of the muscles of the anterior and posterior groups. The largest of these is the brachioradialis muscle. All the muscles of the forearm are involved in one way or another when training the biceps and back.
The back muscles are the second largest muscle group and are subdivided into:
1) Trapezius muscles consist of the lower, middle and upper parts. These muscles give width and mass to your back. In addition, a well-developed midsection “spreads” the shoulders, which makes your shoulder girdle visually wider. The upper part of these muscles plays an important role in supporting the neck and head, and gives the neck bulk.
2) Latissimus dorsi or as they are often called “wings” give width and mass to your back.
3) Back extensors are located along the spine and serve to support it.
4) The rhomboid and infraspinatus muscles are the smallest in this group. They are included in the work when training the latissimus dorsi and trapezius muscles.
The muscles of the legs are the largest muscle group and account for approximately 50% of the total musculature of a person. They are subdivided into:
1) The gluteus muscles are the largest muscles in this group. This is the girls’ favorite muscle group. To achieve elasticity and roundness of the buttocks, most girls go to the gym.
2) Quadriceps consist of four heads and are located on the front of the thigh. It is the most powerful muscle in the human body. In any exercise for the development of leg muscles, all four heads work and receive the proper load at once.
3) Biceps femoris consists of two heads and is located on the back of the thigh. The biceps femoris often lag behind in their development from the rest of the muscles in this group. Due to its location, it is rarely that someone purposefully works out these muscles, but in vain. You will never see large and proportional legs without well-trained biceps femoris.
4) Calf muscles consist of three heads and are located on the back of the lower leg. The most capricious muscles. If you do not have genetically large calves, then you are unlikely to achieve a large volume of this muscle group.
The abdominal muscles provide protection to the vital organs of the abdomen and they are divided into:
1) Rectus abdominis muscle is the desired eight cubes. They develop by bending the body towards the fixed legs, or, on the contrary, by raising the legs to the fixed body. For many athletes, a firm, and most importantly, defined abs is a symbol of excellence. And indeed it is. A beautiful, sculpted abs with well-developed general body musculature looks really great! But do not forget that in order to achieve a defined abs, you mainly need to reduce the total percentage of body fat.
2) Abdominal external oblique muscle is located on the ribs. The best way to work them out is all kinds of twists.
Some facts about muscles and their varieties
Here are some more interesting facts about muscles and muscle groups:
1) In total, a person has from 650 to 840 muscles. During one step alone, the body uses about 200 muscles.
2) Muscle density is 2-3 times more than fat. More specifically, you can tell by knowing where this fat is taken from. Brown (visceral) fat is denser than white (subcutaneous) fat.
3) The heart is the most enduring muscle in the human body. It can work for over 100 years.
4) The sartorius muscle, which is located on the legs, is the longest muscle in the human body. The shortest muscle is the stapedius muscle (located in the ears). The fastest muscle is the blinking muscle, it is located on the eyelids. The most powerful and strong muscles in the human body are the chewing muscles, tongue, calf and gluteal muscles.
5) The recovery time of different muscle groups is different. The triceps are the fastest to recover, but the back muscles are the slowest to recover. You need to know this when drawing up a training program. Muscles need rest no less than exertion. Muscles are able to fully recover from exertion only after 48 hours.
6) Muscles are not eternal. After 40 years, the body begins to burn muscles. In a year, a person begins to lose about 3% of muscle tissue, after 60 years – about 5%. Exercise is just as important in adulthood as it is in youth.