I think it's not based on the breed, more likely on your dog's personality. I mean yeah, some dogs are generally more active than others, but the situations may vary. Some dogs get used to being on the couch for the most of the day, especially if they're in small apartments and then the ones that have grew up in a farm, or some other place like that, tend to run around more.

Our dog is a Papillon and she likes to run around because we live pretty far away from town, so there's a lot of room for her to explore on her own. I heard from somewhere that Papillon as a breed is not that interested in running in the woods, so I think it's all just based on the personality.

Actually, most greyhounds are rather low-key. Just like Great Danes. They don't generally need to be up and at it all the time like Jack Russells or Labradors.

Also, as heavymetalkilos mentioned, there is the component of personality that plays into an animal's activity level. For example, my grandma has a terrier mix that, while she has short spurts of bubbly energy, she tires quickly and returns to sleeping on my grandmother's lap. She's not a very excitable thing, unless you put her in front of squirrels. Then its a whole other story.

I've seen something similar. I'd say that there is a chance that the dog is not getting enough attention or worst case scenario: he's sick, and feels constantly tired, not being able to do the dog-things (running around and having fun).

Although some breeds are generally considered more active than others, every individual dog is still different from another, so it really depends on how the dog's demeanor was when it was still a puppy on how it will behave when adult.