Add Yahoo as a preferred source to see more of our stories on Google. Many of us have felt a muscle in some part of our body suddenly and involuntarily tighten, causing a twitch or even severe cramp.

Though many people experience muscle twitching, it's often incorrectly identified as a muscle spasm. While both are involuntary contractions of a muscle, muscle spasms and muscle twitching aren't ...

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 ...

Most people have likely had the unpleasant experience of a muscle cramp, also known as a charley horse or muscle spasm. And while most cramps will quickly go away on their own, there are a few helpful ...

Myoclonus (pronounced "my-OCK-lo-nus") is a sudden muscle spasm that you can’t control. It can be a natural reflex – like jumping when something scares you or getting the hiccups from laughing too ...

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.