NETA Personal Trainer Practice Exam

In the eccentrically contracting muscle phase, what happens to the muscle?

1. The muscle shortens

2. The muscle remains the same length

3. The muscle lengthens

4. The muscle becomes rigid

The correct answer is: The muscle lengthens

During the phase of eccentric contraction, the muscle lengthens while producing tension. This occurs when a muscle generates force while being stretched, typically against an external load. For example, when lowering a weight or controlling the descent in movements like a squat or a push-up, the muscle fibers are actively engaging, but the muscle as a whole is elongating rather than shortening. This type of contraction is crucial for controlling movement and absorbing forces, thus preventing injury while allowing for smooth transitional movements. In contrast, during concentric contractions, muscles shorten, and during isometric contractions, muscles do not change length at all. Moreover, rigidity is not characteristic of eccentric contractions; rather, rigidity can be associated with other conditions, such as muscle fatigue or spasm. Understanding this detail reinforces the importance of recognizing the different contraction types and their roles in strength training and functional movement.