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

Forty-one-year-old Andres Albaladejo noticed a bizarre symptom in his left arm, which he ignored, thinking it was nothing more than a usual nerve issue. However, little did he know that it was the ...

slow-twitch muscle fibers, which move more slowly but help to keep you moving longer fast-twitch muscle fibers, which help you move faster, but for shorter periods “Twitch” refers to the contraction, ...

When you picture different athletes—marathon runners, gymnasts, and Olympic weightlifters, for example—you likely categorize them instinctively by their height, size, and build. But the differences in ...

Add Yahoo as a preferred source to see more of our stories on Google. Coming to get you. D Simmonds, CC BY-SA In recent years scientists have discovered the many ways that the brain is activated ...