07/19/2008 05:12 am ET Updated Nov 17, 2011

Fitness Fads: Which Ones Actually Work?

From strippercise to circus-trapeze aerobics, gyms and fitness gurus keep coming up with new ways to make working out less of a chore. But though these whimsical classes and instructional DVDs can reinvigorate your gym routine, some of the glitziest (and goofiest) new trends can also put you at risk for sprained ankles, pulled muscles and overexertion. And some don't even give you much of a workout.

Here are seven of the silliest fitness fads--with the lowdown on whether or not they really chisel and tone. (For other workout tips, check out our earlier story on "Six of the Worst Ways to Work Out.")

1. Weighted Hula Hooping. Maybe it was the 50th anniversary last month, or maybe it's the buzz over the new Wii Fit version, but Hula Hooping, the backyard mainstay from the 1950s, is back--and a whole lot heavier. National gym chains like Bally Total Fitness now offer hooping classes to kids and seniors alike, with weighted Hula Hoops that participants wheel around their outstretched limbs and torso.

Will the toy-based hybrid of strength and cardio give you the toned curves of Beyonce, who says she hoops to stay svelte? "The unweighted, traditional ones definitely work your core, and you can actually get the cardio system up," says Jim White, certified fitness trainer and spokesman for the American Dietetic Association (ADA). "I would recommend staying with the normal ones--with the weighted [hoops], beginners could pull a muscle."

The verdict: If you can do it, join the hoopligans. But avoid weighted hoops if you're new, and be advised of the gender divide--White says women are far more likely to be able to hoop well than men.

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