I see many players try to get maximum power by allowing maximum body movement. Unfortunately, it doesn't work that way.
I recall reading a tip book by Billy Casper many years ago. One of the many tips went something like this:
The man who stands still will hit the ball far and true.
It was as true then as it is now. Work hard on keeping your body still. You should really feel as though you are only swinging your arms. The body will follow naturally.
Next time you are out on the course and having a hard time hitting that ball, just think about keeping your body still while swinging your arms. You too will hit the ball far and true.