Start by laying on your back, legs straight out in front of you, guard up, and core engaged. Lift your upper body off the floor, at the same time raising your legs; your goal is a V shaped form. When you’re ready, punch out with both arms towards your toes. Release to your starting position, keeping your legs hovering above the floor to activate your core. Extend your arms out to your toes as you lift your legs into the top of your Jack Knife position. Repeat!