PGen is probably right, most dogs would enjoy it. This dog was about two when we got her and already had some pre-conditioned fears.
She backs off when she hears my electric toothbrush; my guess is that it triggers the sound of vet clippers? She had a serious ordeal with her leg not long before we got her. She's also afraid of the vacuum cleaner; is very wary of moving vehicles.
If/when you decide to look for a dog: see if there are any good prospects at the pound, take it home on a trial basis & test-run it on your treadmill.