ShareHula hooping has remained a staple of modern US culture since the 1950s, but people around the world have participated in similar activities for thousands of years. The physics behind maintaining a perfect spin, however, has remained a mystery. Is it something that can be achieved by anyone with enough time and effort, or are there natural hula hoopers among us? Researchers recently investigated these dynamics using a specially designed, gyrating robotand their findings provide the first-of-its-kind insight into the perfect spin.Seemingly simple toys and games often involve surprisingly subtle physics and mathematics, a team from NYUs Applied Mathematics Laboratory wrote in their study published in the Proceedings of the National Academy of Sciences on Monday. Hula hooping involves these issues and others associated with the rolling point of contact on the body surface, which itself is actuated with gyration motions and whose geometry is expected to strongly affect the hoop dynamics.We were surprised that an activity as popular, fun, and healthy as hula hooping wasnt understood even at a basic physics level, Leif Ristroph, a NYU associate professor of mathematics and senior study author, said in an accompanying statement on Thursday.Successful hula hooping requires a body type with the right slope and curvature. Credit: NYUs Applied Mathematics Lab To learn how various body types influence hula hooping, Ristroph and his team placed multiple 3D-printed models shaped like lightbulbs, hourglasses, rectangles, and other forms roughly one-tenth the size of a human onto a robotic gyrator. They then launched six inch wide hoops onto the shapes while a high-speed video recorded their performance. After analyzing the results, researchers found that getting a hula hoop up and going could be achieved by any of their body shape models.In all cases, good twirling motions of the hoop around the body could be set up without any special effort, said Ristroph.Keeping a hoop going, however, is another matter. To maintain the spin for an extended period of time, a curvier body is often key. More specifically, a form that includes sloping hips that allow an angle to push the hoop, as well as a sufficient waist to sustain the hoop against gravitys pull. Get the Popular Science newsletter Breakthroughs, discoveries, and DIY tips sent every weekday. By signing up you agree to our Terms of Service and Privacy Policy.People come in many different body typessome who have these slope and curvature traits in their hips and waist and some who dont, Ristroph explained. Our results might explain why some people are natural hoopers and others seem to have to work extra hard.The experiments results go far beyond playground pastime strategy, however. Ristroph and his team believe hula hoopings complex, subtle interactions of math and physics could help inspire engineering projects, especially robotics used in industrial processing and manufacturing.