The best exercise for golfers is golfing.
Nicklaus plays a kind of golf with which I am not familiar.
Fight tautness whenever it occurs; strive for relaxed muscles throughout.
No putt is too short to be despised.
I will tell you privately it's not going to get better, it's going to get worse all the time, but don't fret. Remember, we play the ball where it lies, and now let's not talk about this, ever again.
No-one will ever have golf under his thumb. No round ever will be so good it could not have been better. Perhaps this is why golf is the greatest of games. You are not playing a human adversary; you a playing a game. You are playing old man par.