What type of muscle contraction occurs when the muscle shortens during movement at a joint?

The type of muscle contraction that occurs when the muscle shortens during movement at a joint is known as a concentric contraction. This type of contraction happens when a muscle generates enough force to overcome resistance, resulting in movement that causes the muscle fibers to shorten. For example, during a bicep curl when the bicep muscle actively shortens to lift the weight, it is performing a concentric contraction.

In contrast, isometric contraction involves the muscle generating force without any change in length, meaning there is no movement occurring at the joint even though the muscle is activated. Eccentric contraction occurs when a muscle lengthens under tension, typically while controlling the descent of a weight, such as lowering a dumbbell after a bicep curl. Static contraction is synonymous with isometric contraction, emphasizing the lack of movement. Understanding these different types of contractions is essential for comprehending how muscles function during various physical activities.