This exercise is designed to build strength and balance in your core and leg muscles. In the beginning, to help with balance, use a yoga block under your hands. With time and practice, you'll be able to let go, moving your arms out to the sides.
Position a yoga block in front of you, and start by standing upright with your feet together. With straight legs, hinge forward at the hips, rest your hands on the block and raise your left leg behind you. Make sure your left knee is straight, knee and toes facing the floor. Pull your abdominals inward to support the spine. Focus your eyes at one spot on the floor for better balance. Hold this position for 10 to 20 seconds.