You have the basic idea which is good, but you need to refine your animation. Like Tim's Videos said, the movements were very robotic and funky looking. That's because you're make huge movements all the time. There's a time and a place for bigger and smaller movements. It's called easing. You can use easing to make movements seem faster and slower. Right now, everything is moving at a constant pace. This generally doesn't look as fluid/realistic as eased movements. I know that Fancypants has a great tutorial here if you wish to check that out.

Also, the guy in black's fist doesn't connect with the other guy's face. It makes it look very fake just so you know.

Otherwise, just keep going at it.