It kind of makes sense, and I can see why the trainer would think that, but from my reading, a dog will shake when it finds something unpleasant and intense or too stressful.
Quote:
https://www.4pawsu.com/stresssigns.html
Dogs will shake their bodies for a variety of reasons, when they are wet or when they first wake up from a nap. But stress-related shaking off almost always follows something the dog finds unpleasant. For example, many dogs shake off right after a veterinary exam. |
It kind of reminds me human relaxation techniques where we tense everything up and then relax. Try doing a body shake and see if it's not relaxing.