The kettlebell windmill is a fantastic exercise and a lot tougher than it looks.
It combines strength, stability and mobility, especially around the hips, abs, back and shoulders.
It will take quite a bit of practice to master all the little cues but on the whole, the general movement can be performed fairly easily and safely.
The real key is to remember this is about working the muscles in a controlled, safe manner. Not everyone will be able to reach their hand to the floor so work to your individual level.
• Stand tall with feet shoulder width apart. Keep one foot facing forward an turn the other 90 degrees outwards to the side.
• The arm on the side of the foot facing forward, hold a kettlebell and raise directly above the shoulder. Eyes looking straight up at that hand
• Keep both legs straight and the hip of the foot that is facing forward, press that out to the side and lean slightly over
• Press the back of the free hand against the leg
• Bend at the waist and slide the hand down the leg until body is parallel to floor (or as close as is comfortable)
• Stand up tall again and repeat all reps on one side before switching
This is my, mostly, Personal Trainer musings and information which I hope you'll find helpful!