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。

    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.

    但为什么非要去掉跳绳的绳呢？克兰西为此解释到，这对那些不善于跳绳的人来说是个绝佳的锻炼工具。他说：“经常跳绳可以让你的四肢得到充分活动，也有助于心血管的运动，而使用无绳跳绳你就不用担心被绳索绊着而终止跳跃。”

    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."

    克兰西表示，无绳跳绳还可以避免那些精神病患者和罪犯用绳索自杀，而家中的吊扇安装得较低的人也不用担心在家跳绳的不方便了。

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

    然而，对这一发明，加利福尼亚州立大学运动机能学教授恩斯特表示：“这种产品是有可取之处的；但你需要一条绳索才能跳跃吗？其实你不需要。我不会购买这种产品，因为我不是一个白痴。另外，高技术的手柄其实毫无意义，因为你甚至可以手握卫生纸跳动起来。”

    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."