The origin of  kettlebell workouts remains a matter of debate, but there’s no debating the fact that they’re one of the best tools to build muscle and burn fat.

Early in the 20th century, well-traveled strongmen like Eugen Sandow (yes, that Sandow) began featuring kettlebells in their shows. However, subsequent wars caused a divide between Western and Eastern training methodologies, and the humble kettlebell fell out of favor with the training public. Now, of course, they’re back in full force.

“Kettlebells are popular because they are extremely effective and efficient and don’t take up much space,” says Max Shank, a finess author and the owner of Ambition Athletics (maxshank.com).

Shank’s love affair with kettlebells isn’t unfounded. Ask a room full of fitness experts why they like kettlebells so much, and you’re bound to get a host of overlapping answers, ranging from their ability to build strength, power, and mobility to their versatility as a fat-burning, physique-carving wonder tool.

Even better: Science backs up these claims. A 2010 study published in the Journal of Strength & Conditioning Research found that kettlebells provided subjects with a boost in their three-rep-max (3RM) bench press and 3RM clean and jerk, as well as lower-back endurance.

Another study published in the same journal that year showed kettlebells also provide lifters a swift kick to the metabolic gonads, increasing subjects’ VO2 max by statistically significant levels. Similar studies on bells have shown improvements in testosterone and growth hormone release, both of which play a huge role in how big, strong, and lean you can become.

“Some people call the kettlebell the Swiss Army knife of gym equipment,” says Allan Phillips, C.S.C.S., a StrongFirst Level II kettlebell instructor. “You can train many athletic qualities at a very high level using only a single kettlebell. Not many other modalities can match that versatility.”

So if you’re interested in improving your kettlebell proficiency, try one of the routines that follow. Then, once you’re comfortable with the basics, you can try freestyling a few routines of your own. Already a kettlebell connoisseur? Don’t worry, we have a few routines that will challenge you, too.

Kettlebell Swing

The best kettlebell workout

The unique exercise tool adds a new dimension to your workout.

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