For bodybuilders and fitness enthusiasts, changing body composition often reflects hard work and discipline—but knowing body composition is useful for anyone, and for more than just bragging rights.

Uncover hidden health insights that go beyond the scale.

Thanks to the ever-improving world of fitness trackers and apps, you've never had more access to personal health data. But which of the dizzying number of markers and metrics should you really be ...

The Lilliputian tailors measure Gulliver for a new suit of clothing, from Part I of Jonathan Swift's "Gulliver's Travels." (1726) Illustration (1909) by Arthur Rackham (1867-1939) Source: Alamy stock ...