Running with dogs

Hi in your professional opinion what breeds of dog if any could complete a 100 mile ultramarathon at human pace? I am interested in running ultramarathons and I am wondering( not that it is currently allowed) if a dog could ever run a 100 mile ultramarathon with me( at my pace)?

In my opinion, absolutely none.
   
No dog can handle a 100 mile marathon of any kind. No matter how big it is.
   
They are not designed for such sustained running. Dogs run in spurts, then rest for awhile, then trot, etc. Their normal traveling pace is a medium-speed trot, the rough equivalent of a human brisk walk.
   
Humans may be able to push themselves to this kind of extreme, but a dog cannot do it. A 100-mile marathon is no place for a dog.