Also known as "Superman," this move strengthens the muscles in your glutes and core, as well as the stabilizing muscles around your spine to help relieve pressure in the lower back.
How to do it: Get down on your hands and knees with your palms flat on the floor and shoulder-width apart. Brace your abs, and raise your right arm and left leg until they're in line with your body. Hold for 5 to 10 seconds. Return to the starting position. Repeat with your left arm and right leg. Continue to alternate until you've completed 10 reps on each side.