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 ...

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 ...

Want to drop a size in time for summer? Welcome to the first week of the Get Healthy for Summer Challenge, the ultimate shape-up plan to flatten your belly, firm your thighs and get you swimsuit ready ...

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 ...

Brains improve not by ease, but effort followed by recovery 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 ...

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 ...

University of Pittsburgh provides funding as a member of The Conversation US. If you have ever lifted a weight, you know the routine: challenge the muscle, give it rest, feed it and repeat. Over time, ...