How to fix annoying dog habit of blocking me when I’m walking through the house.

For reference – the dog is not mine, it is my roommate's, and is a five year old heeler. (~45lbs)

I will try to do a simple task, like walking through a doorway, or going into the kitchen. This dog will decide that it wants attention, and will walk over and stand right in front of my legs – fully blocking me from walking. He knows many commands, including lay down, back up, etc., yet absolutely nothing besides taking it to a near aggression level will make this dog back off. He's not aggressive in any way, just effectively making himself into a wall and not going away.

I've literally tried anything/everything I can think of – calmly yet firmly telling him to back up, go lay down, etc., trying to nudge him in the direction he needs to go to get out of the way, yelling, treats, literally everything. He has dog beds in every room and can easily lay down/get out of the way if he decided to – so how does a person convince a 5 year old dog to cut this crap out?? And once again, it's not my dog – and I can't change or control anything its actual owners do, I'm just trying to learn a method to get him out of the way when I need to, without having to resort to angrily yelling at this dog to get him to move out of the way!

Edited to add; walking into the dog over and over again isn't an option, as I have arthritis and bad knees & hips, so it causes me actual physical problems, and I've done this dozens of times already throughout the years, and it has no effect on the dog, he doesn't care.