Вот пример не только тренировки, но и врожденного синдрома гипермобильности суставов! Ross Sisters, 1949 год

The Ross Sisters were a trio of female sibling singing dancers consisting of Aggie Ross, Elmira Ross, and Maggie Ross, (whose real names were Veda Victoria, Dixie Jewel and Betsy Ann Ross). The Ross Sisters performed as a 3-part harmony trio, in which they also danced and did acrobatics and contortionism. Their public attention peaked during the 1940s, during which they were featured prominently in the film Broadway Rhythm. A shortened version of this same clip also appears in the compilation film “That’s E