Академия русского балета имени А. Я. Вагановой
After the war, Sizova studied at the Vaganova Academy of Russian Ballet, where she was taught by Natalia Kamkova. Among her classmates was Rudolf Nureyev, with whom she performed the "Le Corsaire" duet in a school graduation film, which attracted the attention of the Kirov Ballet. The two were recruited by the Kirov directly as soloists.