Most everyone has experienced anxiety at some time, whether it be jumping out of a bad dream with your heart pounding, or (most people) have felt nervous when anticipating talking in front of a group of people.
I've used those comparisons when explaining to my Father (the last 16 years I've had anxiety and agoraphobia). Except for me, and many other anxiety sufferers, that climax doesn't always even out like with someone who doesn't suffer anxiety attacks. I explain it's exhausting physically, mentally and emotionally to feel thay way on a constant basis.