I take Gracie and Boodah on 3-4 long walks a day. If not they drive me crazy. They start by whining at me, then barking if I ignore them. A sure sign that they have not been exercised enough is the way Gracie will start shredding things in the house such as toilet paper and paper. We have a very large yard that is not fenced in (lots of hawks), so we walk them on leash all the time.
They get a 4 acre walk in the morning and at least two or three 4-6 acre walks throughout the evening.
Only then do I have happy yorkies