Super Banana Drill
Here is a drill we picked up from a workout video that I like to use at the end of a core workout. In this video the guys are on their 4th set of 1 minute goes (out of 5)with a 30 sec rest.
Start in the "superman" position, with only your abs on the ground, arch backwards with your haed off the mat, and arms and legs lifted up.
without letting your legs or arms touch the mat roll over to the "banana" position, arms and legs locked straight with your body curved upwards.