Dorsil raises are great for lower back exercise.

1. Start by laying with your face down on the floor. Your legs, shoulders and arms in line with one another, keep looking at the floor.
2. Lift you hands up and place them next to your temples( just next to the ear)
3. Breath in lift both head and arms together, hold this position for two seconds then release exhale out and relax bring your body  back  to the floor.