Take this passage from the Spring and Autumn Annals of Mr. Lu: "During the time of Yin Kang, because the people were melancholy with their bones and tendons inactive, people were encouraged to dance."
《呂氏春秋》有云：「昔陰康氏之時，民氣鬱遏，筋骨不達，故作為樂舞以宣導之。」