What occurs during eccentric action in muscles?

Eccentric action in muscles refers to the process where a muscle is activated and creates tension while simultaneously lengthening. This occurs when the load on the muscle exceeds the force the muscle can generate. For example, during activities like slowly lowering a weight or going down stairs, muscles such as the quadriceps lengthen as they work to control the descent against gravity. This action is essential for deceleration, controlling movements, and providing stability to the joints.

The correct choice highlights that, during this type of muscle contraction, the muscle acts as a resistive force while it lengthens, which is key to understanding how muscles work under load and play a crucial role in movement dynamics. Eccentric contractions are important not only for performance in athletic endeavors but also for injury prevention and rehabilitation, as they help in strengthening the muscle and its associated tendons while allowing for controlled movement.