"Hearst Magazines and Yahoo may earn commission or revenue on some items through the links below." If your body were a bicycle, your abs and back muscles—your core—would be the frame. You need a ...

There are two kinds of people in this world: People who want to work their core and people who consider core exercises their worst nightmare. But regardless of which camp you fall into, if you are ...

Beth Skwarecki is Lifehacker’s Senior Health Editor, and holds certifications as a personal trainer and weightlifting coach. She has been writing about health for over 10 years. It’s kind of strange, ...