It seems Chrissy Teigen has developed an unexplained ailment. The model, who is one of the judges on NBC's new comedy show, Bring the Funny, premiering tonight, took to Twitter to explain what exactly ...

Fast twitch muscles help with sudden bursts of energy involved in activities like sprinting and jumping. Twitch muscles are skeletal muscles that help support your movement. They’re especially ...

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Building your fast-twitch muscle fibers can help you get stronger and faster. This type of muscle fiber is responsible for the fast, explosive movements used in activities like sprinting, jumping, and ...

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. A common ...

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 ...

The ninth-grader started getting dizzy spells and headaches two weeks ago. Then about a week ago, her right hand started twitching, she said. The twitching seemed to start in her wrist, then move up ...