Tweaked by a muscle twitch? From an uncontrollable fluttering eyelid to a pulsing calf muscle, these small, rapid involuntary muscle contractions may happen at any time -- and can be annoying.

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 ...

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We've all been there before. Running along the basketball court or swimming across the pool, when, all of a sudden, we experience a sharp pain in our foot or leg. Muscle cramps are common, affect ...

Medically reviewed by Smita Patel, DO Hypnic jerks are sudden muscle contractions that happen as you fall asleep. They are ...

Medically reviewed by Nicholas R. Metrus, MDMedically reviewed by Nicholas R. Metrus, MD Almost all of us will have experienced a fasciculation at one time or another. A fasciculation is simply a ...

After a grueling CrossFit workout on a hot Summer morning that involved kettlebell swings, goblet squats, and about 100 walking lunges, my lower body was toast. But what was weird was that my left ...

‌Hemifacial spasm is a disorder of the nerves and muscles that causes nonpainful involuntary twitching on one side of the face. Many people refer to hemifacial spasms as lip muscle spasms. Hemifacial ...

Twitching at night—it’s something few of us talk about, yet it’s also a phenomenon that impacts Americans when it comes to sleep quality. And even if you feel like you’re getting enough sleep, you ...

You’re sitting at your computer when it starts — that annoying flutter in your eyelid that feels like a tiny butterfly trapped under your skin. Most of the time, eye twitching is harmless and goes ...