Here is a great video of some work Grayson Murray and I did at Old Palm. I use lots of resistance bands to help players engage their body and create feels they can use to make changes in their swing. This one is excellent if you have an unstable lower body, too loose and long of a back swing or struggle sliding during the back swing.
Try this on the range and see if you don’t have a more stable supportive lower body and an improved back swing!
Tighten up your backswing video tutorial