Stability ball plank knee tucks
Complete 3 sets of 10. Remember this is a plank so the rear doesn't raise up as the knees tuck in towards the chest. Exhale brings knees in, inhale brings you back to plank.
Complete 10 circles in each direction and repeat twice. Shoulder blades come off the ground while chin and eyes gaze up towards the ceiling. Exhale brings shoulders off mat and inhale circles you back to the ground.
Complete 2 sets of 20. This is an extended version of a bicycle movement except it's harder because all limbs are straightened. Botton leg extends towards the ground as long as the low back can remain on the floor. If not don't lower leg as low to the ground. Opposite arm reaches up towards opposite foot. Inhales and exhales move you from one side to the other.
Pike's with Socks (or TRX with feet in handles of TRX)
Complete 3 sets of 10. Because you are in plank pull the belly button in towards the spine. Exhale brings hips towards ceiling and inhale brings you back to plank.