What type of contraction occurs when a muscle lengthens and generates force?

The correct answer is eccentric contraction. An eccentric contraction occurs when a muscle generates force while it lengthens. This type of contraction is commonly seen when a muscle is under tension as it yields to a greater external force, such as when lowering a weight or during activities like running downhill. During this process, the muscle fibers lengthen, but they are still able to create force, which helps control the movement and stabilize joints.

This is crucial in various physical activities and sports, as eccentric contractions play a key role in deceleration and controlling motion, ultimately contributing to overall muscle strength and joint stability. Understanding eccentric contractions is important for designing effective training programs and rehabilitation exercises, as they also help to develop strength endurance and prevent injuries.