In what way is a wolf's body structure better than a human's body structure?
I think what you mean here is better adapted, rather than better for the habitat in which wolves live and for the niche that wolves fill in nature. A wolf and a human carry out different roles in nature.
The wolf is a predator of such organisms as deer, moose, buffalo, beavers and others. Its body contains sharp curved canine teeth for tearing flesh and back teeth capable of chewing through bones. Humans have small canine teeth which are not curved or as strong as a wolf's. Their tongue is rough compared to that of a human and is adapted to help them scrape meat off bones while eating.
Their feet contain claws and fleshy paws to help travel through snow. Their front feet are wider than their back feet and they possess long legs. Because they tend to hunt during night hours, they have excellent night vision. They are also able to smell and hear more than humans are able to. They don't see well in color and are more adapted to see far and sense motion. This enables them to track and kill prey. They possess ears covered in fur.
Wolves are covered in a thick coat that provides protection from the elements, keeping them both warm and dry. This coat is colored for camouflage, as it is usually brown or gray with black and white hairs mixed in. The upper layer is coarser and contains guard hairs which help to keep the wolf dry. It is usually oily. In winter there is a thick coating of fur beneath the upper layer to provide added insulation.
Wolves are social animals that hunt in packs. They use their large brain, specifically their cerebrums, to help them to engage in pack activities. Humans, however, have a superior intellect to wolves and a larger cerebrum to body size.
The limbs of wolves have radius and ulna bones (as do humans) however theirs are in the locked position which enables them to have greater ability to be fast, agile and stable while running.
Both humans and wolves are mammals and share many homologous structures, which points to their common ancestry. However, during the course of evolution, these structures have become fine-tuned to enable these organisms to fulfill their subsequent roles in nature.