As we get older, all of our backswings shorten as we loose mobility of the core muscles. The good news is that quality of lag is not predicated on the length of the backswing. One can have great lag on a chip or even a putt with a very short backswing. Sounds like most seniors, you might be concerned with loosing distance. I have lots of ways to increase distance, but finding what’s right for you is personal and can only be accomplished with my personal help.