Building muscles: Muscle stem cells (their nuclei marked in blue) gradually alter their structure and function, becoming adult muscle cells (whose nuclei turn red). Those cells will eventually fuse ...

If you have ever lifted a weight, you know the routine: challenge the muscle, give it rest, feed it and repeat. Over time, it grows stronger. Of course, muscles only grow when the challenge increases ...

Changing your rep range and your workout intensity can help you build more muscle, says an exercise scientist with decades of ...