The binasuan is a Filipino folk dance in which the performer holds full wine glasses in each hand while performing balancing tricks.
The arms are rotated over and under the shoulder in order to keep the palms facing up so as not to spill the liquid while nevertheless allowing the radius to cross over the ulna via pronation.
Binasuan originated in Pangasinan and is popular at festive events such as weddings.
Upon a rotation of 4π radians, the palm "doubly covers" the shoulder, and the elbow points in its original direction.
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