A small amount of muscle tension and muscle definition (the appearance of muscle beneath the skin) is present even in a relaxed muscle. A person who is physically fit due to regular exercise, will have more of this characteristic of muscle tissue than someone who is not fit. What is this characteristic?

Answer: Muscle tone

Explanation: Muscle tone is actually a muscle tension. This tension (muscle tone) maintains the body in its position as it is, or in a particular desired position. Or, for example, during movement, when the body changes its position, these changes of position are regulated by muscle tone. When the body is at rest, some muscle tension exists, and depending on the general fitness of the body, that tension under the skin is more visible or less visible, that is, my muscles will be tighter or floppy.