This is a demonstration that shows proper form and movement. I love this exercise because it works most of your body and requires no equipment to do it…just your body weight.
Get into a lunge position and “scissor” jump onto the opposite leg. Lift your hands over your head and bring your stationary knee forward at the same time that you’re lowering your hands and don’t forget to crunch your abs. Then jump back to the other side and repeat the knee raise/crunch.