
The kettlebell windmill is a wonderful exercise for the core musculature. Think of it as a twisty good morning. Not only is it a great stretch for the posterior chain (erector spinae, glutes, and hamstrings), it is also a strength builder for the transverse abdominis and internal oblique. When starting, choose a lighter weight and move up only when you’ve developed enough flexibility to get the raised arm perpendicular to the floor.
They feel great the next day in that wonderful, achey along the whole length of my spine way.
Nice!