The back consists of large, complex muscles that support your trunk and spine. There are many types of back muscles, and they are all essential, helping you walk, bend, twist, and hold your body ...

Muscle contraction is the tightening, shortening, or lengthening of muscles when you do some activity. It can happen when you hold or pick up something, or when you stretch or exercise with weights.

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 ...

Plus, how it differs from strength training and expert tips to program workouts for both approaches.