A hula hoop is a toy hoop that is twirled around the waist, limbs or neck. Although the exact origins of hula hoops are unknown, children and adults around the world have played with hoops, twirling, rolling and throwing them throughout history. Hula hoops for children generally measure approximately 71 centimetres (28 in) in diameter, and those for adults around 1.02 metres (40 in). Traditional materials for hoops include willow, rattan (a flexible and strong vine), grapevines and stiff grasses. Today, they are usually made of plastic tubing. Plastic hula hoops are often filled with rocks or materials which serve as weights to carry the hoop around the body. Hula hooping has been a type of exercise and play from as early as the 5th century in ancient Greece. Before it was known and recognized as the common colourful plastic toy (sometimes with water inside the actual hoop), it used to be made of dried up willow, rattan, grapevines, or stiff grasses.
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