As I try to improve at golf, I realize that my focus has historically been completely on the technical components to have a better golf swing.  This has proven to be difficult, I believe in large part due to my fitness and flexibility.  This winter, I have focused on improving these components.  One easy drill I do is a core strengthener in the video below.  I try to do the "Par" version of this at least twice a day.  As my strength, fitness and flexibility improve I feel this will make swing changes significantly easier.