You've certainly seen these spherical weights in the gym. They have handles and come in a variety of sizes and weights. People are swinging them all around...but what's the kettlebell craze all about?
Kettlebells have developed from the Russian military who have used a similar cannon ball technique for years. One of the biggest benefits is combining muscular endurance with cardiovascular training making for an all in one for the time crunched.
In so doing, you're working balance, coordination, muscular strength and endurance and your heart rate is up there as well. The proponents really like the whole body approach the kettlebell workout offers.
Depending on your personal joint issues, and your specific goals, the kettlebell may or may not have a place in your program. Any kettlebell workout should be done with a certified instructor, and specifically with someone who understands your joint issues.
Take the photo for example. Her squat position is decent, although her chest could be more upright. As she moves to her upright position her shoulders are impinged, her trapezius is doing all the work, and her quads are disengaged. Her shoulder joint is in a compromised position.
These tools can be used individually, or in a group setting. Like anything, it's not something to become competitive with in terms of how much weight you can swing around. Each of us has our own abilities and limitations.
Is it for everyone? Not in my opinion. This is something which has been developed for athletes, for law enforcement and for elite populations. It wasn't developed for general population use, and most people I know will tell you about their latest shoulder injury at the drop of a hat.
Can it be used safely. Sure, under strict guidance from someone who is trained and knows what they are doing. You can incorporate it within a certain range of motion for your ability, under supervision.
Like anything, it is a tool to add variety. But I do cringe most times I see someone pick one up and swing it around. Then I duck and take cover!