You're relaxing on the sofa when suddenly your eyelid starts twitching. Or perhaps it's a muscle in your arm, your leg, or ...

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.

Muscle twitching is often caused by stress or a lack of sleep and is usually not serious. If muscle twitching occurs with muscle weakness or wasting, you should see a doctor. Muscle twitches can be ...

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 ...

When you buy through links on our articles, Future and its syndication partners may earn a commission. Credit: Getty Images It tends to happen when you’re just about to drift off where your legs or ...

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 ...

It’s the most common sleep disorder you’ve probably never heard of: restless legs syndrome. RLS affects up to 10% of the population and can cause nagging pain and discomfort along with an ...

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 ...

Fast-twitch fibers help with explosive movements like sprinting and weight lifting. Genetics and training influence the distribution of fast-twitch and slow-twitch muscle fibers. Doing strength ...

Infectious agents can cause muscle twitching and spasms, too. The most commonly known is probably tetanus, which causes a phenomenon called lockjaw, where the neck and jaw muscles contract to the ...