Grizzly bears protect themselves with their sheer strength and massive paws. They are also fast runners that can sprint up 35 miles per hour. They also swim quickly and can swim away from danger.
When attacked by a pack of wolves, which generally involves the wolves nipping quickly at the grizzly's hind legs, the grizzly sits down and protects itself in a circle.
Female grizzlies can be fierce when they feel as if their cubs are threatened, or if they are protecting their food. Human attacks by grizzly bears is rarely because the bear sees the human as food, but instead because the bear feels threatened or is surprised at a close range.