The American Council on Exercise (ACE), America’s authority on fitness and one of the largest fitness certification, education and training organizations in the world, recently came out with a study examining the benefits of kettlebell workouts. ACE Fitness found subjects burning an average of 20 calories a minute with a kettlebell snatch routine, which is a much higher-intensity workout than standard weight-training routines. Also the heart rate and VO2 responses during the exercises indicate an intense workout similar to running at ‘6 minute mile pace’ explains John Porcari, Ph.D at University of Wisconsin, La Crosse Exercise and Health Program. These results show that kettlebells, when used properly offer superior results in a short amount of time.
For more information about the study http://www.acefitness.org/getfit/research.aspx
Caution! I am thankful that ACE came out with these results and put positive publicity on kettlebells. That being said, please do not attempt the exercises they have listed without proper instructional guidance. I really would have liked to see a progression for beginners to work on stabilization exercises with the kettlebells in their article. The instructions, pictures and target muscles listed in that section are not sufficient. The picture of a kettlebell deadlift looks more like a squat and they even omit hamstrings as a target muscle!
I recommend reading clarification from a more seasoned kettlebell professional
For functional workouts using kettlebells with proper instruction, as well as safe progression from beginners to athletes visit Monkey Bar Gym