"Hearst Magazines and Yahoo may earn commission or revenue on some items through these links." All it takes is a tweak or two, and virtually any exercise for any muscle group can instantly become a ...

All it takes is a tweak or two, and virtually any exercise for any muscle group can instantly become a core movement as well. It's all about positioning. One great example of this is the V-sit ...

Don't just sit there! Try this amazing ab exercise. It's a one-minute challenge combining two classic core moves: the V-sit and the Russian twist. Trust us — you're going to love it. But if you hate ...

To chisel your abs and strengthen your core, add some dumbbells to your core workout. Adding some weight forces the fibers in ab muscles to activate more fully, making each rep more effective. This ...