Well, there's a reason why it doesn't look like her. She is moving in action, and its a screen "grab", so it turns out all blurry. Myuu, or however her name is really spelt, is also very flexible. So, I think that one is actually of her.
But usually, it isn't hard to spot the stunt doubles, just about most scenes that can be remotly dangerous to do, its a stunt double. Sad, I would want to do my own stunts