My last yorkie (RIP Brandi) was extremely laid back. She liked nothing better to be in my lap all day and night. She never over exerted her self. She probably was the only dog that never panted that's because she didn't believe in running!
Whenever she got tire of walking, would come to a complete stop and I would have to carry her.
Duchess my current yorkie is on speed. In fact she only knows two speeds fast and faster. I am convinced that she was speedy gonzales in another life. She is probably the only pet that I have that never sleeps. Even when she is resting her eyes are open mainly because she is so nosey and has to investigate every little noise she hears.