Bare Foot Kettlebell?
 

I have been enjoying Kettlebell workouts. I noticed all of the instructors are bare footed during the exercises. Best form when using kettlebell? It probably activates your core more having to balance with the 'imbalance' nature of kettlebells.

It is definitely recommended to be barefooted or in something that allows you to feel the ground for kettlebells. I think it has to do with proper form and being rooted to the ground etc., but I can’t remember. I know Lauren Brooks talks about this somewhere. It’s how I judge if someone actually knows how to properly instruct kettlebells though or is just pretending to when I’m on youtube etc. I know Pavel, the kettlebell godfather, says barefoot is best or Vibram shoes, the ones that go around all your toes, are ok.

I've done all ways (bare, Vibram, running shoes, training shoes (weight training shoes). Running shoes are definitely NOT ideal due to the cushioning. You need stability when doing KBs. When I do these outside the house (public gym), I wear either my Vibrams or my Nike 360s, which have stability built around the entire foot. Both work. Barefoot is easier to maneuvering moves such as Turkish getups and clean and jerks.

I do kettlebell workouts barefoot, but then again, I do all workouts barefoot (on yoga mat on top of puzzle mats). I only wear shoes for hiking and sometimes for walking -- if the weather is warm enough, hiking sandals or supportive flip flops from Chaco and Teva do the trick! I had PF/flat feet, and years of yoga and barefoot workouts have helped. My physical therapist has recommended I do lower body exercises to strengthen my patellofemoral syndrome-affected knees with supportive shoes on (i.e. with Superfeet insoles... which can fit into Vibram-like minimalist shoes) but I've been trying to get by without 'em. This is probably one reason why I never took to step aerobics -- too much fuss to get shoes on and all the noise on the step when I'm stepping on and off, combined with knee issues.