Back press
Start face down, hands behind head. Lift your chest off the ground as far as you can, and hold for 10 seconds. Keep looking at the floor, to avoid straining your neck. Then lie back again. You can tuck your feet under something to hold them down, or you can lift your feet at the same time as you lift your head and chest.
Variation: Adding a twisting movement, to raise one elbow high rather than both, brings other lumbar muscles into play.
Muscles trained:
Primarily erector spinae and related muscles responsible for holding the spine upright and for arching the back.
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