Final answer:
An isometric contraction is a muscle contraction that produces tension without changing the angle of a skeletal joint. This type of contraction is important for maintaining posture and stability.
Step-by-step explanation:
An isometric contraction occurs when the muscle produces tension without changing the angle of a skeletal joint. In this type of contraction, the muscle length remains the same while muscle tension increases. Isometric contractions are active in maintaining posture and bone and joint stability.
For example, holding your head upright requires isometric contractions.