It's no secret that workouts and music are pretty much the best pairing since peanut butter and jelly. There's nothing like putting in your headphones, cranking it up and just totally losing yourself during some intense cardio. (Indoors only, of course! Leave one earbud out if your sweat sesh is outdoors.) But we know it's not always easy coming up with that perfect mix to get you in the zone, and, even when you do, it doesn't take long for that Kelly Clarkson jam to go from making you run that extra mile to making you want to run off a cliff. You gotta keep it fresh to keep yourself motivated, right?