Going harder, better, faster, stronger is sometimes just what you need to take your fitness game to the next level—and that’s where interval training comes in. It’s designed to get you fit and burn fat faster (in fact, there’s a whole slew of studies that support just how awesome it is).

And though it’s easy to find a class that offers interval training at a studio or a gym, sometimes it’s just not in the cards to pack into a room with fellow fitness junkies—much less leave your house. The good news? You don’t always have to. YouTube has plenty of easy-to-follow interval training routines that you can do in your own living room. These 14 videos will boost strength and get your heart pumping, anytime, anywhere.