Hooping is likened to yoga and is regarded as a fun way to get a cardio workout. A class in Manhattan. Yana Paskova for The New York Times

When Karl Lagerfeld introduced his ridiculously oversize hula-hoop beach bag at a Chanel runway show recently, he inadvertently struck a pop-cultural chord.

Among the most talked-about accessories to emerge from this season's shows, the beach bag seemed to have tapped into a newfound affection for the hula hoop, as a fashion statement and an exercise device.

A video of Mr. Lagerfeld explaining the bag ("It's for the beach. You can put it into the sand and hang things on it.") has been popping up on fashion sites like Fashionista and Styleite. And Chanel announced that it would be selling smaller versions in stores.

Actual hula hoops have received celebrity endorsements. Christie Brinkley was photographed hula-hooping in Times Square on October 5 for World Smile Day, an event that promotes acts of kindness. Television talk show host Jimmy Fallon challenged Michelle Obama to a hula-hooping contest on "Late Night With Jimmy Fallon" in February, after she was photographed hooping on the White House lawn at her Healthy Kids Fair.

"A lot of people are interested in hooping for its health benefits, which might get them hooked, but it's also such a fun way to do cardio," said Bex Burton, a hula hoop instructor who founded Sense of Motion, a Brooklyn-based company that also teaches Pilates and yoga.

As with any exercise trend, accessories have proliferated. "We just got in a beautiful prototype of a goatskin-covered hula hoop - it's dark black leather with a nice grip," said Gabriella Redding, founder of Hoopnotica, a fitness company near Venice Beach in Los Angeles that sells hoops and certifies 300 instructors a year to teach "hoop dance."

Sales passed the $1 million mark last year, Ms. Redding said. Buyers include Stefan Pildes, a founder of Groovehoops, a hoop performance troupe in New York that offers classes.