This exercise works your core, obliques and abs. It is a challenging exercise. Position yourself in a side plank with your feet stacked together and your elbow directly under your shoulder. Place your left hand on your hip and slowly lift your hips off the ground and slowly bring your right knee into your chest and hold. Hold the position keeping your hips off the ground. Hold for 30-45 seconds and change sides. As you get stronger you can hold the pose for 1 minute.