Which term describes a muscle contraction that maintains the same length?

The term that describes a muscle contraction that maintains the same length is isometric. In an isometric contraction, the muscle generates tension without changing its length. This means that even though the muscle is active and working, there is no movement at the joint. This type of contraction is often used in various types of strength training exercises where stability is required or when a position needs to be held, such as during a plank position in Pilates.

Concentric contractions involve shortening of the muscle as it contracts, while eccentric contractions involve lengthening of the muscle under tension. Isokinetic contractions are characterized by a constant speed of contraction throughout the range of motion, which does not align with the concept of maintaining muscle length.