Muscle contraction is the tightening, shortening, or lengthening of muscles when you do some activity. It can happen when you hold or pick up something, or when you stretch or exercise with weights.

Using powerful new visualization technologies, researchers have captured the first 3-D images of the structure of a key muscle receptor, providing new insights on how muscles develop across the animal ...

The flow of water within a muscle fiber may dictate how quickly muscle can contract, according to a new study. The flow of water within a muscle fiber may dictate how quickly muscle can contract, ...