Ark effortlessly lifts that guy up and sets him back.
I'm just catching up on some of this thread, but to be fair, it's not that Akuzawa lifts that guy all on his own. Nor I think it was his goal to have the holder respond in that exact manner. The guy holding is adding a lot to the direction he ultimately takes. He is taken up and to the rear and since he doesn't want to fall awkwardly (and has no chance of keeping his shoulders down), he tries to get the rest of his body back in order and in balance, and ends up with a "seiza hopô".
If the guy was a statue, Akuzawa's push back wouldn't have been so dramatic, or if the guy was just a bag of potatoes, he would have just slumped backwards. In any case it takes two-to-tango, your mileage may vary, etc.
So, to ask someone to replicate certain results, requires a certain amount of similar circumstances/constraints/controls, etc. All other things being equal that is, such as skill.