Kettlebells. You’ve probably seen them in magazines or mentioned around the gym lately, but what the heck are they? Do they make noise like a bell? What’s so great about them, anyway?

A kettlebell is a large round weighted ball with a handle attached to it. Kettlebells were developed by Russian strongmen in the early 1700s as a way to quickly build strength, balance, flexibility and endurance.

“Quickly” is the key here. Studies have shown that you can get twice the workout in half the time by incorporating kettlebells into your routine.

Kettlebells are a prime example of the saying “what’s old is new again.” Kettlebell fitness classes are popping up in gyms across the nation. And yes, you can even find them locally.

I have talked in the past of how efficient interval training is for burning off fat and for getting a most efficient workout, and kettlebell training does just that.

Kettlebell workouts vary, but the one common theme is explosive power movements performed with the massive ball. These movements increase your heart rate by asking your body to move the weight quickly through space. Think of bounding up the steps as opposed to stepping. You are applying that type of movement through all your muscle groups; you use your leg muscles to move your upper body.

Kettlebells come in a variety of different sizes, usually in 5, 8, 10, 15, 20, 30 and 50-lb increments. You sometimes use only one kettlebell at a time for the exercises and incorporate lots of repetitions (up to 30), or the exercises can be performed in timed sets. So you could do one exercise for one to two minutes with no rest. Kettlebell exercises work all body parts and should not be performed every day.

In a recent research study by the American Council on Exercise, a 20-minute kettlebell workout burned off as many calories per minute as running at a six-minute-mile pace. That is extraordinary! That is more than 20 calories per minute!

So the bottom line: if you’re someone who doesn’t have a lot of time, kettlebells allow you to get in a good workout as quickly as possible.

Try it out sometime, and let me know what you think of kettlebell training. Is this a workout trend that is bound to stick?