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 ...

Warming up before exercise may not increase your overall strength, but new research shows it gives your muscles the speed and explosive power needed for rapid movements. Study: The effect of muscle ...