Start in a plank position with your hands directly under your shoulders and sliders under the balls of your feet.
Do not allow your lower back to arch. Keep your feet, pelvis, and shoulders in one long line. On an exhale, pull your abs deeply to your spine and use your abs to fold your body in half, pulling the sliders forward toward your hands as your pelvis moves up in the air.
Lower yourself back into a plank position, and do not allow your pelvis to sag below your shoulders. This is one rep.