This exercise is great for your neck muscles.
To perform it you will need a plate and a flat bench.
Lie face down on the flat bench. Your shoulders are about even with the end of a bench.
Place a plate on the back of your head and hold it in place with your hands.
Slowly raise your head up as far as comfortable. Slowly return to starting position.
Exhale as you raise your head up and inhale as you return to starting position.