Are pull ups as performed by Oliver Queen in the TV series The Arrow possible? Referring to the pull ups performed by Oliver Queen in the TV series The Arrow.

My hunch is that such pull ups are impossible because it violates the law of physics: as Oliver tries to pull himself up, his hands applies forces on the bar, and therefore his hands can no longer lift the bar up simultaneously. 
Am I right about this?
 A: It is possible, and somewhat standard cross-fit exercise called Salmon Ladder.
https://www.youtube.com/watch?v=IPGqgmS981E
There is nothing unphysical. From physics perspective, there is two situations. One, where the bar is supported. Then he pull himself up and the bar is standing still between the supports. The supports provide external force countering the downward pulling force of the chinupper. Then, when he takes the bar off the hooks, the system is isolated and total momentum can no longer change except for the downward pulling gravity. However, the bar does not weight all that much, and it can easily be pushed up, much faster than the gravity starts do pull the chinupper down. The speed is of course the key here. The total momentum of an isolated system without external forces cannot change, but momentum transfer can be between the two subsystems (person and the bar).
A: That's exactly what he's saying, is that it's not physically possible. But as we all know it is. Think about it. As he pulls down forcefully on the bar and lifts himself upward, if he gathers enough momentum he should be able to lift the bar up with him, as long as it's not bolted in or something.
