What's the first thing that comes to mind when you think about the words twitch and muscle? Spasms, perhaps. You'd hardly be alone in thinking that. But when it comes to fitness, it's most commonly ...

Ever wonder why some people seem to pack on muscle effortlessly while others spend months in the gym with little to show for it? Muscle growth isn't just about lifting weights -- it's a complex ...

Type IIb fast-twitch myofibers, known for their rapid contraction speed, are plentiful in small mammals but have largely diminished in humans. Researchers at the University of Tsukuba have discovered ...

This article was originally featured on The Conversation. Usain Bolt, the world’s fastest human, ran a 100-meter sprint at a speed of 23.35 miles per hour (37.57 kilometers per hour). That’s ...

Everyone is familiar, at least hand-wavingly, with the distinction between slow-twitch and fast-twitch muscle-fiber types. The former are great for running marathons; the latter are ideal for ...