What does "muscle tone" refer to in skeletal muscles?

Muscle tone refers to the continuous and passive partial contraction of skeletal muscles. This state of partial contraction is important because it helps maintain posture and provides stability to the joints, even while at rest. Muscle tone is not associated with voluntary movements or active contractions, but rather describes a baseline level of tension in the muscles that is necessary for maintaining an upright position and readiness for action.

Unlike active contraction during exercises, muscle tone represents a state of readiness rather than exertion. It is also distinct from complete relaxation of muscles, which would mean no tension at all. Furthermore, muscle tone does not pertain to the maximal contraction force, as this concept involves the greatest amount of force a muscle can produce during a contraction, typically seen during strenuous activities. Thus, the correct understanding of muscle tone focuses on the state of readiness and stability provided by the continuous, albeit passive, contraction of muscles.