Remember how alive and energized you felt after your first week of yoga or Spinning classes? In an effort to recapture that bliss, you've stuck to the same routine ever since, setting yourself up to hit a fitness plateau, burn out, or — even worse — suffer a debilitating injury.

“We're creatures of habit, so the routine is easy,” says Christopher Mohr, RD, an exercise physiologist and dietitian in Louisville, Kentucky. “But a routine means you'll never grow fitter; your body needs constant change to progress.”

With help from some of the top fitness experts in the country, we put together a simple plan that will fit easily into your lifestyle, whether you've been exercising for five weeks or five years. Try it; your body and your mind will be glad you did.

The VIP Moves

Next page: Cardio Rut-Busters