Rock 'N Roll
Tuck chin inward to chest area, curl the spine and gently rock/roll as shown in these photos.
Form check: use your knees and thigh muscles to "push" against your hands to initiate the "curl". Continue 4 to 8 times, you should feel the spine muscles begin to relax and get warm as circulation increases. For those who are a little more advanced, try to pause as you roll up without touching feet to the floor and extend head upward with chest forward and shoulders back.