Come into an all fours position on an exercise mat with your hands directly under your shoulders and your knees directly under your hips. Lift your knees a few inches off the floor and move both feet back a few inches. This is your start position. Keeping your core braced and a neutral spine, push off explosively from the balls of your feet, elevating your hips towards the sky, bending at the knees and driving your feet up overhead until the touch your glutes. Land gently on the balls on your feet. Repeat.