A good way to think of paddling is to compare it to ballroom dancing - the man's side if he is doing it right. When dancing, we maintain a nice erect posture. We use our arms pretty much like struts to signal to our partner where we want to go. We don't crush her hand, we have a nice relaxed grip.  We try to keep an eye on where we are going so we don't run into other obstacles (dancers for instance). Although we are sitting in a kayak, the basics are pretty much the same. This approach makes good use of our core muscle groups instead of pulling with just our arms. Here is a great article on paddling posture and the Paddler's Box: Paddling Posture.