And for that idea kicking around Clancy's head since 1988, the U.S. Patent Office this month awarded the 52-year-old Mansfield, Ohio, man a patent. Its number: 7037243. What makes this invention work is the moving weights inside the handles. They simulate the feel of a rope moving, Clancy said.

But why jump rope without a rope?

It's perfect for the clumsy, Clancy said. "If you are still jumping, you're still using your legs as well as your arms, and getting the cardiovascular workout. You just don't have to worry about tripping on the rope."

It is also good for mental institutions and prisons where rope is a suicide risk, said Clancy, who works as a laundry coordinator¹ in a state prison. And low ceiling fans aren't a hazard any more, he said.

The idea isn't all that crazy, said Mike Ernst, a professor of kinesiology at California State University in Dominguez Hills.

The more he thought about it, the more Ernst said he could see the benefit, adding that ,"Do you need to jump with a rope? You don't," Ernst said. "But I wouldn't buy the product, I can tell you that. I'm not an idiot."  

High-tech² handles aren't needed. You could even use toilet paper holders³, Ernst said. On second thought, he wondered if he could patent that idea.

中文简译：

　　俄亥俄州的发明者克兰西从1988年起便产生了发明这种无绳跳绳的想法。本月，美国专利局对52岁的Clancy颁发了无绳跳绳专利证书。克兰西介绍说，无绳跳绳手柄中可以移动的重物会让使用者觉得是有绳索在移动。