A very dynamic shot with a great sensation of motion conveyed. However, IMHO I feel like it would be better if the camera angle were higher. Say, just over the shoulder showing some of the face. It is fundamentally a very sound shot. It's just that, for me, the hand and knee aren't as interesting as seeing some of the face. Maybe that's just me. I love the idea and the execution though. You certainly captured the essence of motion in this shot.