Vöðvatónus

Vöðvatónus refers to the slight, continuous contraction of muscles that occurs even when a muscle is at rest. This resting tension is crucial for maintaining posture, stability, and readiness for movement. It allows muscles to respond more quickly to stimuli and maintain body shape. Without vöðvatónus, muscles would be flaccid and unable to support the body or initiate actions effectively.

This phenomenon is controlled by the nervous system, specifically through reflex arcs. Sensory receptors in the muscles, known as muscle spindles, detect changes in muscle length. When a muscle is stretched, these receptors send signals to the spinal cord, which then triggers a motor response to contract the muscle, counteracting the stretch. This maintains a baseline level of tension.

Variations in vöðvatónus can indicate different physiological states or neurological conditions. For instance, increased muscle tone, known as hypertonia, can be seen in conditions like spasticity or rigidity, making muscles stiff and resistant to movement. Conversely, decreased muscle tone, known as hypotonia, results in muscles being too relaxed and weak, often seen in infants or certain neurological disorders. Proper vöðvatónus is essential for coordinated and efficient movement.