The weight of a kettlebell hangs from the handle, rather than being centered on the handle as with a dumbbell. This one feature causes the location of the mass to change more during movement.
Why should I train with Kettlebells?
More muscle engagement during use than other forms of weight training
If you do a lifting, twisting or swinging movement with a kettlebell, you will notice that the inertia and changing location of the mass relative to your body requires much more muscle engagement than if you perform the same motion with a dumbbell. Not only are more muscles engaged during the movement, but more muscles are required to stop the movement! Much higher involvement and effort is required from your core, your stabilizing muscles and your grip during a kettlebell workout.
You can do almost every dumbbell exercise with a kettlebell, but you can only do many kettlebell exercises with a kettlebell. Plus kettlebells can be used for one-or two-handed movements.
Kettlebells help you break out of the boredom that comes from doing the same dumbbell or barbell exercises over and over again.
Friendly note: Train smart
Before starting a kettlebell routine, consult the training materials like that offered in this catalog in order to learn proper form and technique. Start light to ensure you can safely maintain control during use. And have fun!