You can find this exercise on page 33 of the book Synergistic Golf.
Exercise Type: PILATES
Exercise Category: ABDOMINALS, BALANCE, HIPS, LOW BACK, STRENGTH
Lie on back with both knees bent and feet hip distance apart. Place arms face down at sides. Inhale. As you exhale, imprint your spine flat to the floor as you tuck your pelvis and roll your spine one vertebrae at a time off the floor up into a straight bridge. Inhale at the top then exhale as you roll your spine back down to the floor pulling your hips toward your heels. Variations; at top, lift one foot off floor at a time without moving pelvis.