"Hearst Magazines and Yahoo may earn commission or revenue on some items through the links below." If you've completed a core workout—or 100 of them—over the years, you likely know what crunches are ...

Our core muscles are essential to everyday movement; we need them to walk, sit, and to lift and carry things. If you don’t do them right, you will likely feel tension in your neck, so be sure to use ...

For core workouts from Stephanie Mansour — plus fitness challenges, walking podcasts, meal plans and inspiration — download the Start TODAY app! When it comes to toning the abdominals, many of my ...