Get down on your knees and forearms, elbows shoulder-width apart, knees under hips and toes curled under. Inhale, then exhale as you tighten your abdominal muscles without moving your back. Slowly lift both knees at the same time, floating them a few inches off the floor [shown].
Hold for 1 full breath while pressing into your forearms and squeezing abs tightly. Lower both knees at the same time. Do 4 to 8 reps, resting in between by sitting back on your heels if necessary.