Muscle breakdown means that a muscle becomes measurable and sometimes visibly thinner and loses strength. Very roughly one can subdivide the muscle into two main structures. These are, on the one hand, the structures that can actively contract (contract) and, on the other hand, the passive tissue, which includes the tendons and the sheaths of the entire muscle and its subunits. Primarily, the muscle breakdown in the contractile elements takes place. The predominant process is a decrease in the cross-section of the muscle fibers, secondarily a reduction in their number.
Two mechanisms must be intact for a muscle to function properly. On the one hand, this is the function of the nervous system, where impulses are generated and directed to the muscle. On the other hand it is the perfect function of the muscle itself. He must be able to receive and process the incoming stimuli and he must be able to contract.
The stimulus absorption takes place in the so-called motor end plates. From there, the incoming impulse is channeled through certain channel systems to the muscle interior, where it leads to a calcium release into the cell interior. If the concentration is high enough in the sarcomeres, the smallest functional units in the muscle cell, a contraction occurs under energy consumption in which the sarcomeres are shortened or put into increased tension.
The primary task of a muscle, in addition to heat production, is the development of force through contractions. The stronger the stimulus that passes through the nerves to the muscle, the more sarcomeres in the millions of muscle fibers become strained and the greater is the development of strength in the entire muscle. Frequent and intensive use of the muscle can increase strength by increasing the cross-section of the muscle fibers.
The resulting force is transmitted via the tendons on the approaches to the bone. The train either creates a movement in the involved joints or leads to an increased tension. In the first case, the muscles perform dynamic in the second static work. The activity is directed by the target programs in the brain. This results in finely tuned motor patterns in which the acting muscles either act as opponents or as teamworkers.
When an impulse from the brain initiates movement in a specific joint, it automatically activates all the muscles necessary for it. The opponents (antagonists) are inhibited. This mechanism is important for optimal movement function.
If the antagonists also tense, this would hinder the movement. Flowing coordinated movements would not be possible then.
Static muscle work is always required when it comes to stabilizing certain joints or body regions. Known examples of this are the stabilization of the trunk and the spine during dynamic activities of the extremities or the knee stabilization in the standing position. Especially with slightly bent knees, it is important that agonists and antagonists work together. The main active controlling muscles in this case are the knee extensors. They control the stand and prevent a collapse of the legs. At the same time, however, the knee flexors are required to keep the position of the two joint partners in the optimum range. This prevents excessive stress on the articular cartilage and menisci.
The condition of a muscle depends on whether it is used or not. If external or internal factors mean that it is not or only rarely used, it will lead to muscle loss.
The "normal" degradation process of the musculature begins at the age of 25 years, if the person is not actively counteracting. In low-active women and men are every decade of life lost on average 5 - 10 percent of muscle mass. The process accelerates again significantly when it reaches the age of sixty. The result is an overall reduced performance, which is noticeable when climbing stairs, for example, or when a sporting activity is performed. Regular physical activity can significantly slow down the degradation process. An entry in the higher age is quite useful.
Muscles degrade very fast if they stop for a while or permanently. It forms a so-called inactivity atrophy out. The muscle becomes measurably and visibly thinner and loses strength and function; the efficiency drops. Typical causes of this process include immobilization of a part of the body following injury, or inactivity of the entire skeletal muscle due to bed-rest as a result of illness or age. If the causes of atrophy are eliminated, the affected muscles can be rebuilt through training. However, the construction is tedious and takes much longer than the mining.
In bedridden people not only the skeletal muscles, but also the respiratory muscles and the muscles of the internal organs are degraded. As a result, in addition to the motor function and the functions of the affected organs are affected.
Certain illnesses and injuries can cause the muscle to stop working and break down. A typical injury sequence is paraplegia due to spinal cord transection. Individual peripheral nerves can also be injured and result in paralysis of the supplied muscles.
Genetic disorders known as muscular dystrophy damage the musculature itself or its conduction system. As a result, it comes to muscle loss and an increasing reduction in performance, sometimes with premature death.Tags: