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 ...

There can get a point where you’re climbing mountains, navigating rough terrain, or carving fresh pow and feeling good —but ...

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 ...

Usain Bolt, the world’s fastest person, ran a 100-meter sprint at a speed of 23.35 miles per hour (37.57 kilometers per hour). That’s mind-blowingly fast for a human. It’s about the same speed as ...

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 ...

Your running speed partly comes down to factors you can't control, like genetics, and partly relies on your training. When you purchase through links on our site, we may earn an affiliate commission.