Add Yahoo as a preferred source to see more of our stories on Google. Though many people experience muscle twitching, it's often incorrectly identified as a muscle spasm. While both are involuntary ...

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 ...

You're in the middle of your squat reps — weight in hand — and just like that, a charley horse causes your calf muscle to go rogue. When this type of muscle spasm or cramp hits, there is no mistaking ...

Doctors identify these movements as 'fasciculations', because they occur when individual nerve fibers, which control small muscle groups activate independently to produce brief muscle contractions.