It takes some time. One time I took in a male Dalmatian. He was a good little dog(smaller than the female Dalmatian I had). That dog was super strong. I thought I should enter him in one of those dog pulling contests. Anyway when I first got him, every time I would raise my hand he would cringe. His eyes would be squinting. So I figure someone had been beating him. He was a sweet dog,not aggressive to people or other dogs. I started raising my hand and then giving him a piece of hot dog. Shortly after the cringing stopped. Then a little longer and he quit squinting. He could still pull you down in the yard if you were not careful. He had very big feet for a small dog and he could grip the ground. I believe he could pull a pickup truck in neutral if you needed a tow. David