Muscle tone: causes, complaints and therapy
Muscle tension, also called muscle tone, describes the state of tension or the internal tension of a muscle or a muscle group - at rest, in motion, during exertion or even under stress.
Muscle tone - basic tension
When people sleep, the muscles are relaxed. This is not the case during the day. When people are awake, even when they are at rest, there is always muscle tension, even if only a few muscle fibers are tense. Muscle tension does not always have to cause movement, but is then referred to as basic tension without it. It is necessary so that people can sit or stand upright, which usually does not cause any effort. Keeping your head straight is also part of this basic tension. Without muscle tension, humans cannot move. A certain muscle tone is a requirement, especially for coordinated movements and fine motor skills.
Prolonged muscle tension, which is also painful, is called muscle tension. This arises from stereotypical, one-sided or incorrect posture, stress, trauma and much more. Most people are familiar with the symptoms when, for example, sitting on a PC for a long time hurts the neck or hurts the back after a long drive.
Active and passive muscle tone
In medicine, a distinction is made between active and passive muscle tone. A passive muscle tone or a passive muscle tension depends on the nature of the tissue structures, the composition of the muscle fibers, the anatomical position of the muscle, the blood supply and the oxygen supply. An active muscle tone is noticeable through its contraction - the contraction of the muscle.
Striated muscles - smooth muscles
The skeletal muscles consist of striated muscles. This is subject to the will. The muscle tension arises here from the successive contractions of individual muscle fibers. On the other hand, the smooth muscles that are located in the intestine, for example, cannot be addressed arbitrarily. The muscle cells of the smooth muscles are permanently contracted, which creates the corresponding muscle tension.
Nothing works without energy
Energy is required to create muscle tension. A quarter of the energy required already uses the basic tension of the muscles. Even more energy is then consumed during active muscle movements. This is especially well-known among athletes: the more muscles there are, the more calories are burned, even when at rest. If someone wants to lose weight, he would do well to build muscle mass. Wherever energy is consumed, there is also heat, including here when the muscles are consuming energy. This is important for your own body heat.
Muscular dystonia is a disturbed muscle tension. This can mean both reduced and increased tension in the muscles. If there is no longer any muscle tension at all, there is paralysis, also known as flaccid paralysis. The motor nerves of the affected part of the body are out of action here. Another disorder is paresis. The motor nerve pathways have failed in some cases, but the basic tension is often retained. Paralysis is accompanied by a massive decrease or even a total loss of muscle strength in the affected area. This can be temporary, but it can also be permanent.
Muscular hypotension also belongs to muscular dystonia. Here the muscle tone is reduced. The basic tension decreases somewhat, but is not completely disturbed. The causes of this are a stroke, traumatic bleeding in the cerebellum or multiple sclerosis. This hypotension manifests itself, for example, by an abnormally strong swinging of the arms.
Furthermore, increased muscle tension is possible - in the form of spasticity or rigidity. In spasticity, the increased muscle tone is such that the affected extremities get into an unnatural position. With rigidity, on the other hand, the muscle tension is so high that this leads to stiffening.
Muscle relaxants are medications that reduce muscle tension. Relaxants with peripheral effects are used, for example, during anesthesia or during operations. Central muscle relaxants work in the central nervous system. They are used for tension or spasms in the area of the striated muscles, for example in the presence of a cervical spine syndrome (symptoms: pain, discomfort in the neck and shoulder area). These drugs are often prescribed along with pain relievers for massive muscle tension.
Examination of muscle tone
At night, when we are asleep, the muscles are relaxed. During the day, even at rest, some muscle fibers are always in tension. However, these small contractions do not lead to any movement. In order to examine muscle tension, the movement of individual joints is passively checked on the relaxed patient. Passive means that the patient does not move and only the doctor performs certain movements with the joints.
For example, if there is a spasticity in which the muscle tone is increased, the symptoms become more severe the faster the movement is carried out by the practitioner. If the muscle tension is reduced, this becomes visible through slack swinging with passive movement. (sw)
Author and source information
This text corresponds to the specifications of the medical literature, medical guidelines and current studies and has been checked by medical doctors.
Susanne Waschke, Barbara Schindewolf-Lensch
- Claudio L. Bassetti, Marco Mumenthaler: Disorders of muscle tone (muscle tension), neurological differential diagnosis, Thieme Verlag, 6th edition, 2012
- Klaus Buckup, Johannes Buckup: Clinical tests on bones, joints and muscles, Thieme Verlag, 5th edition, 2012
- Hans-W. Müller-Wohlfahrt, Peter Ueblacker, Lutz Hänsel: Muscle injuries in sports, Thieme Verlag, 3rd edition, 2018