What Are the Functions of the Muscles in the Human Body?

Muscle (muscle), mainly composed of muscle tissue. Muscle cells are slender and fibrous, so muscle cells are often called muscle fibers.

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Human muscles are about 639 pieces. It is composed of about 6 billion muscle fibers, of which the longest muscle fiber is 60 cm and the shortest is about 1 mm. Large muscles weigh about two kilograms, and small muscles weigh only a few grams. The average person's muscles account for 35 to 45 percent of body weight.

It can be divided into different structures and functions.

Each muscle that makes up a motor organ is a complex organ consisting of two parts, the abdomen and the tendon.

Muscle abdomen

The muscular abdomen is the main part of the muscle organs, located in the middle of the muscle organs, and is composed of many skeletal muscle fibers connected by connective tissue. With shrinking ability. The connective tissue that surrounds the entire surface of a muscle is called the epidural. The outer myometrium extends inward and divides the muscle fibers into muscle bundles of different sizes. This is called the myofascial myometrium and extends inward to surround each muscle fiber, called the endomysium. The sarcolemma is the supporting tissue of the muscle, giving the muscle a certain shape. Blood vessels,

There are many principles for naming muscles, mainly including: according to shape, such as trapezius muscles, triangular muscles; according to position, such as superior muscles, inferior muscles, anterior tibial muscles,

Blood supply

The blood supply of muscles is abundant, and it is compatible with the strong metabolism of muscles. Each muscle has its own blood supply. The main blood vessels are mostly accompanied by nerves. They travel along the muscle space and fascial space. The branches enter the muscle from the muscle door, and branch repeatedly in the muscle. Finally, the muscle fiber is formed to surround the muscle fibers. Capillary network flows from the capillary network into the venules and venules out of the muscular portal. According to the source, location, thickness, number of branches, primary and secondary blood supply of muscle and meat, the blood supply of muscle and meat can be divided into 4 types: Single nutrient artery type: pressure is supplied by a thicker artery For a whole muscle, the arteries enter the muscle from the proximal end of the muscle, such as the broad fascia muscle, the gastrocnemius muscle, and the lateral head. Double nutritional artery type: This muscle has two nutritional artery supply of similar diameters, such as gluteal muscle, straight abdominal muscle, straight femoral muscle and so on. Main vegetative arteries plus secondary vegetative arteries: The muscle has a large vegetative arteries and some smaller secondary arteries, such as trapezius muscles, latissimus dorsi and so on. Segmental nutrition arteries: Muscle meat is supplied by several thinner arteries. The arterial stem of the limb sends branches into the muscle from different planes from the starting point to the stopping point of the muscle. Anterior tibial muscles, long toe muscles, etc. The blood supply of muscular tendons is less. The sources of blood supply are as follows: longitudinal muscles in the interfascicular connective tissue that continue through the muscle-tendon junction; many small branches from interstitial vessels; muscles Blood vessels from the bone and periosteum at the tendon stops.

Lymphatic reflux

The lymphatic return of the muscles begins with the capillary lymphatics of the muscles. They are located in the muscular fascia of the adventitia of the muscles. After leaving the muscles, they accompany the venous return and merge into the larger deep lymphatics.

Innervation

The nerve branches that innervate muscles are called muscle branches. Except for the abdomen and deep back muscles that are segmentally innervated, most of the other muscles are mostly innervated. The nerve source, running and entering muscle parts of muscles are more constant than blood vessels and have less variation. They are accompanied by the main nutritional blood vessels of muscles, and they are basically the same. The nerves that innervate muscle usually contain both sensory and motor nerve fibers. The sensory fibers transmit the pain and temperature of the muscles and proprioception, the latter mainly senses the changes in muscle fiber contraction and contraction, and plays an important role in regulating muscle activity. Motor nerves are responsible for the contraction of muscle fibers and maintaining muscle tension. A synaptic connection is established between the distal end and the muscle fiber, which is called the motor endplate or neuromuscular connection.

Overview

Muscle assist devices are

From now on, we will focus on skeletal muscles. The basic molecular processes are the same in the three muscle types.

Skeletal muscle is also called striated muscle because

significance

The muscles under the skin are a magic engine. It allows us to walk, jump, and even climb steep rocks. The body's 600 muscles work together to help you through every day.

Muscles help us fight gravity. Muscle fibers control every movement, from blinking lightly to smiling, thousands of tiny fibers are assembled into muscle bundles to form a complete muscle system. Take climbing enthusiasts as an example, every step up requires the muscles to be stretched tightly. Muscles can only pull, not push, most of them belong to skeletal muscles. They are connected by tendons and bones, and the tightly bound tendon fibers have the function of rubber bands.

Muscles can move eyeballs, allowing us to see clearly, winking, and blinking; the muscles of the hands and fingertips allow us to pinch very small objects. Take climbers as an example. To climb, they need to hold things to fix themselves. Continuous muscle contraction can keep them climbing up.

We can decide when and how skeletal muscles are affected, but we are not always aware of this change. Sometimes you may adjust your posture slightly to maintain balance, but you may not have noticed this change in posture, and this dynamic balance is always happening. But there are also muscles that we cannot control at will-the digestive system. There are many involuntary muscles there. There are three types of non-voluntary muscles in our stomachs (inclination, middle ring and outer longitudinal smooth muscle) responsible for crushing food. There are two types in the small intestine, which are responsible for squeezing food like a snake and then stretching it forward. Involuntary muscles also help our heart beat continuously. The heart muscle has only one thing going on in our lives: transporting blood.

After a certain amount of exercise, muscles can become developed. But must big muscles be good? the answer is negative. Capillaries are responsible for carrying red blood cells through the muscles. When the muscles contract violently, the capillaries are squeezed, the muscles begin to lack oxygen, and waste begins to accumulate. However, under extreme stress, muscles cannot respond quickly, and fatigue continues to strike.

Take rock climbing as an example. A muscular, strong male climber might think that he has been climbing all the way up, so he will climb quickly. But the muscles of his forearm would soon be deficient in oxygen, forcing him to give up. Faced with certain physical challenges, women have an advantage over men. Rock climbing is more about a person's strength to weight ratio. Small muscles are more beneficial, just bear your own weight. Women with smaller muscles exert less force and squeeze the capillaries lighter, so the muscles have more endurance.

Chest training

Bench press

Starting position: Lie on a bench with the barbell over the nipple.

Action process: Raise the barbell vertically until both arms are fully extended, the chest muscles are completely contracted, stand still for one second, and slowly fall.

Breathing method: Exhale when lifting, inhale when falling.

Points to note: Be careful not to use too much resistance. Use less force in the first few times and increase it gradually to avoid neck sprains. Do not allow any rotation of the neck.

Upright bench press

Starting position: Recline the bench 30-45 degrees with your head up, and hold the barbell with your hands above your chest.

In situ.

Breathing method: Exhale when lifting, and inhale slowly when falling.

Down recline

Starting position: recline the bench with the head down and hold the barbell with your hands under your chest.

Breathing method: Exhale when lifting, and inhale slowly when falling.

Supine bird

This action directly exercises the chest muscles, and can be used in the supine, upper and lower reclining positions.

Starting position: lying on a supine bench with two hands facing each other, holding dumbbells; arms straight up and perpendicular to the ground, and feet flat on the ground.

Movement process: With both hands falling to the sides, both elbows are slightly flexed until they cannot be lowered. Let it stand for a second to allow the pectoralis major muscles to fully extend, then raise your arms from both sides up to the starting position.

Breathing method: Inhale when both arms are pulled apart and exhale when recovered.

Points to note: Do not hold hands tightly. When you split your arms, tighten your back muscles. The idea is focused on the contraction and extension of the pectoralis major muscle.

Horizontal straight arm pull up

Starting position : On a supine bench, holding dumbbells or barbells in both hands, arms straight out, parallel to the ground. Step your feet flat on the ground or on a bench.

Movement process: Keep both arms extended flat, will pull the dumbbell or barbell up and down, and fall to the lowest point possible. Let it stand for a second and let the pectoralis major muscle stretch as much as possible. Then, contract the pectoralis major muscles and pull both arms up and forward until they fall to the starting position on the side of the leg.

Breathing method: Inhale when pulling upwards and backwards, exhale when returning upwards and forwards.

Points to note: When pulling back, let both arms extend straight back, and when pulling forward, let both arms extend straight forward. This action can also be performed by holding a heavy dumbbell in both hands, because the grip distance between the two hands is narrow, and the weight is concentrated in the center of the bar, which has a greater effect on the development of the pectoralis major muscle near the centerline of the human body.

Abdominal training

The abdomen is at the very center of the body and is a particularly noticeable part. From the perspective of human bodybuilding, a truly bodybuilding abdomen should be composed of thin and powerful waists and clearly defined abdominal muscles. Therefore, please do not ignore bodybuilding exercises for the abdomen.

First, bend sideways

upright. Separate your legs, lift your arms left and right, bend your upper body forward, use your left hand to reach your right foot, and lift your right arm naturally. Do not bend your legs and arms. Inhale, then restore, and exhale. Change direction again and repeat 8 times.

Second, leg flexion

Supine position. Keep your arms flat against the ground from side to side, straighten your legs and lift your knees, inhale, bring your thighs close to your abdomen, then exhale and slowly return. Repeat 8 times.

3. Lift your abdomen

Mainly exercise the lower abdominal muscles. Lie on your back with your legs straight and raised as far as possible, and then slowly lower it. After this exercise, bend your knees and continue to do the same. Repeat 8 times.

Fourth, sitting bent

The supine position is mainly to exercise the upper and lower abdominal muscles. Straighten your legs, lift your back, keep your body balanced, then bend your knees and abdomen, making the abdominal muscles extremely flexed. During practice, your feet should never touch the floor or the bed.

V. " Bicycle" exercise supine position.

Take turns flexing and stretching your legs, imitating the movement of cycling, and move quickly and flexibly. The range of flexion and extension should be as large as possible. It lasted for 20 ~ 30 seconds.

Six, twist the waist exercise

Hold the handle in one hand or pull a heavy weight, and perform twisting and turning exercises in various postures to exercise the external oblique and waist muscles.

Each of the above exercises can be selected according to their own conditions, and the amount of each exercise is gradually increased from small to large according to the physical condition, and is performed twice a day.