Instead of running on a treadmill, path, or track, Caldiero prefers trail running for up to 40 minutes. "It's better on your knees to run on dirt, and you're building coordination skills needed for the obstacles. Jumping off rocks targets different stabilizer muscles that you don't normally develop running on the ground," he says. Not into running? Moravsky also plays basketball for cardio, coordination, and to keep his legs in shape.