Sit-ups often come to mind when you think about working your abs or strengthening your core. It’s one of the most old-school, well-known exercises for ab-shredding, but recently, it’s become less and ...

Beth Skwarecki is Lifehacker’s Senior Health Editor and has been writing about health, fitness, and science here since 2015. Beth was the recipient of the 2017 Carnegie Science Award in science ...

In the workout below, Tamir demonstrates different variations of the crunch and the sit-up, including how to do both traditional moves properly. He says practicing cross-body exercises like the ...

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 ...

Refreshing your workouts prevents boredom and training plateaus, but you don’t always need to program brand-new exercises to stay in the game. Sometimes you can just as effectively switch up your ...