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

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 ...

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 ...

Why are we asking for donations? Why are we asking for donations? This site is free thanks to our community of supporters. Voluntary donations from readers like you keep our news accessible for ...

Clonus reflex is a set of rhythmic, involuntary muscle movements. It is a neurological condition that affects the nerve cells that control muscle movements. Damage to the nerves, as in clonus, causes ...

Using powerful new visualization technologies, researchers have captured the first 3-D images of the structure of a key muscle receptor, providing new insights on how muscles develop across the animal ...

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.