This exercise strengthens core stability muscles of the neck. Lying down with your knees bent place a small towel behind the arch of the neck. Next, press the tip of the tongue up against the roof of the mouth and do a chin nod. It will feel like you are giving your self a double chin. Then pivoting off the towel, slightly lift the head off the mat while keeping the lower back flat. Next, bring your arms up while keeping the chin nod engaged and the lower back flat. With your fists shoulder width apart slowly bring them apart even more for another for 5 seconds and then take 5 seconds to slowly bring them back up to the start position again. Do 15 repetitions of this for 3 sets. This is great for neck injuries such as whiplash, acute and chronic neck strains and headaches caused from neck injuries. "