HOWEVER: Swings can cause major back injuries if not done correctly so can many other kettlebell exercises especially when using heavy weights.
I have no idea why i feel the need to share this, but I didn't listen to Chrissy and am currently in my third week of intense back pain. Two doctors visits, muscle relaxers, pain pills. stretching... nothing has helped. I hurt it using a mere 15 pound kettlebell. Things were going great the first few weeks, and then I tried bending more at the waist and... ouch. So yes, be careful. Just glad it was me and not the DD.