This exercise adds lateral spine flexion to the lift of both legs. It will increase engagement for the entire lateral side of the body.
To do this exercise you will need a mat. Start by lying on your side with your head, ribs, hips, and heels in a line. Find the longest possible spine and inhale into the back of the ribs. As you exhale reach your head and your heels away from each other and then allow your legs and shoulders to rise into the air as your body bends into a bow like shape. Inhale as you release and the repeat 8-10 times.
Things to think about
Reaching the head away from the tail will put tension (the good kind) on the lateral myofascial line of the body. This prevents any crunching on the side of the body, which will cause strain.
Be aware of your neck in this exercise. The cervical spine is the most mobile and thus will try to do the work of the entire spine. Be sure that the lateral flexion is also in the thoracic spine as well.