I am 10 sessions into a long term comittment, with a personal trainer, to getting in shape. 1 hour sessions, 3 times a week, MWF. I am 66 years old, but according to her, in pretty good shape due to golf, dancing, and staying active. She is varying the exercises as we progress. She has a plan that appears to be working.
A couple of sessions ago, she introduced the Kettlebell. The video in this thread is exactly what we did. Talk about finding muscles you didn't know you had. She says we will be using KB to work on specific muscles involved in swinging a golf club.
After this short time, the change in the tone and strength of my core and quads is amazing. Can't wait until golf season starts up in a few months.