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.

MICKLETON, N.J. (WPVI) -- Nearly everyone gets a muscle cramp from time to time. When muscle contractions won't stop and can't be controlled, that's called dystonia. A South Jersey man is now sharing ...

At one point or another, we’ve all experienced the unexpected, intense pain of a muscle cramp. Muscle cramps, also known as muscle spasms or charley horses, are the involuntary contraction of muscle ...

In a serendipitous discovery, UC San Diego researchers using cryo-EM technology captured the first visualizations of the 3-D structure of the muscle acetylcholine receptor in fetal and adult muscles.