A new book on willpower asserts that it's a muscle. That is, you can strengthen it with practice, and you can exhaust it with stress and overuse. This makes sense, and years of research back the idea.

Find out about the benefits of working out with a long-lasting disease and how to exercise safely.

How do our muscles respond at the molecular level to exercise? Researchers have unraveled the cellular basis and signaling pathways responsible for the positive impact of physical activity on our ...

The battle against age-related muscle loss doesn’t have to be a losing one. After 30, adults typically lose 3% to 8% of their muscle mass each decade, but the right exercise combination can ...